diff --git a/src/ImageSharp/PixelFormats/Bgr24.cs b/src/ImageSharp/PixelFormats/Bgr24.cs
index 955b5c161..b099bab1c 100644
--- a/src/ImageSharp/PixelFormats/Bgr24.cs
+++ b/src/ImageSharp/PixelFormats/Bgr24.cs
@@ -14,22 +14,25 @@ namespace SixLabors.ImageSharp.PixelFormats
     /// Ranges from [0, 0, 0, 1] to [1, 1, 1, 1] in vector form.
     /// </para>
     /// </summary>
-    [StructLayout(LayoutKind.Sequential)]
+    [StructLayout(LayoutKind.Explicit)]
     public struct Bgr24 : IPixel<Bgr24>
     {
         /// <summary>
         /// The blue component.
         /// </summary>
+        [FieldOffset(0)]
         public byte B;
 
         /// <summary>
         /// The green component.
         /// </summary>
+        [FieldOffset(1)]
         public byte G;
 
         /// <summary>
         /// The red component.
         /// </summary>
+        [FieldOffset(2)]
         public byte R;
 
         /// <summary>
diff --git a/src/ImageSharp/PixelFormats/Rgb24.cs b/src/ImageSharp/PixelFormats/Rgb24.cs
index fa03683c6..c540a7d12 100644
--- a/src/ImageSharp/PixelFormats/Rgb24.cs
+++ b/src/ImageSharp/PixelFormats/Rgb24.cs
@@ -15,22 +15,25 @@ namespace SixLabors.ImageSharp.PixelFormats
     /// Ranges from [0, 0, 0, 1] to [1, 1, 1, 1] in vector form.
     /// </para>
     /// </summary>
-    [StructLayout(LayoutKind.Sequential)]
+    [StructLayout(LayoutKind.Explicit)]
     public struct Rgb24 : IPixel<Rgb24>
     {
         /// <summary>
         /// The red component.
         /// </summary>
+        [FieldOffset(0)]
         public byte R;
 
         /// <summary>
         /// The green component.
         /// </summary>
+        [FieldOffset(1)]
         public byte G;
 
         /// <summary>
         /// The blue component.
         /// </summary>
+        [FieldOffset(2)]
         public byte B;
 
         /// <summary>
diff --git a/src/ImageSharp/Processing/Quantization/FrameQuantizers/WuFrameQuantizer{TPixel}.cs b/src/ImageSharp/Processing/Quantization/FrameQuantizers/WuFrameQuantizer{TPixel}.cs
index fbc40dc8a..bc7a2df71 100644
--- a/src/ImageSharp/Processing/Quantization/FrameQuantizers/WuFrameQuantizer{TPixel}.cs
+++ b/src/ImageSharp/Processing/Quantization/FrameQuantizers/WuFrameQuantizer{TPixel}.cs
@@ -157,13 +157,13 @@ namespace SixLabors.ImageSharp.Processing.Quantization.FrameQuantizers
             }
             finally
             {
-                this.vwt.Dispose();
-                this.vmr.Dispose();
-                this.vmg.Dispose();
-                this.vmb.Dispose();
-                this.vma.Dispose();
-                this.m2.Dispose();
-                this.tag.Dispose();
+                this.vwt?.Dispose();
+                this.vmr?.Dispose();
+                this.vmg?.Dispose();
+                this.vmb?.Dispose();
+                this.vma?.Dispose();
+                this.m2?.Dispose();
+                this.tag?.Dispose();
             }
         }
 
diff --git a/tests/ImageSharp.Tests/Formats/Jpg/JpegDecoderTests.Baseline.cs b/tests/ImageSharp.Tests/Formats/Jpg/JpegDecoderTests.Baseline.cs
index 778459775..f178c29c0 100644
--- a/tests/ImageSharp.Tests/Formats/Jpg/JpegDecoderTests.Baseline.cs
+++ b/tests/ImageSharp.Tests/Formats/Jpg/JpegDecoderTests.Baseline.cs
@@ -42,7 +42,7 @@ namespace SixLabors.ImageSharp.Tests.Formats.Jpg
         public void DecodeBaselineJpeg_PdfJs<TPixel>(TestImageProvider<TPixel> provider)
             where TPixel : struct, IPixel<TPixel>
         {
-            if (TestEnvironment.RunsOnCI && !TestEnvironment.Is64BitProcess)
+            if (SkipTest(provider))
             {
                 // skipping to avoid OutOfMemoryException on CI
                 return;
diff --git a/tests/ImageSharp.Tests/Formats/Jpg/JpegDecoderTests.Progressive.cs b/tests/ImageSharp.Tests/Formats/Jpg/JpegDecoderTests.Progressive.cs
index 83983691e..c988f8f05 100644
--- a/tests/ImageSharp.Tests/Formats/Jpg/JpegDecoderTests.Progressive.cs
+++ b/tests/ImageSharp.Tests/Formats/Jpg/JpegDecoderTests.Progressive.cs
@@ -18,7 +18,7 @@ namespace SixLabors.ImageSharp.Tests.Formats.Jpg
         public void DecodeProgressiveJpeg_Orig<TPixel>(TestImageProvider<TPixel> provider)
             where TPixel : struct, IPixel<TPixel>
         {
-            if (TestEnvironment.RunsOnCI && !TestEnvironment.Is64BitProcess)
+            if (SkipTest(provider))
             {
                 // skipping to avoid OutOfMemoryException on CI
                 return;
diff --git a/tests/ImageSharp.Tests/Formats/Jpg/JpegDecoderTests.cs b/tests/ImageSharp.Tests/Formats/Jpg/JpegDecoderTests.cs
index cfd5989f5..3667790a2 100644
--- a/tests/ImageSharp.Tests/Formats/Jpg/JpegDecoderTests.cs
+++ b/tests/ImageSharp.Tests/Formats/Jpg/JpegDecoderTests.cs
@@ -48,11 +48,13 @@ namespace SixLabors.ImageSharp.Tests.Formats.Jpg
             string[] largeImagesToSkipOn32Bit =
                 {
                     TestImages.Jpeg.Baseline.Jpeg420Exif,
-                    TestImages.Jpeg.Issues.BadZigZagProgressive385
+                    TestImages.Jpeg.Issues.MissingFF00ProgressiveBedroom159,
+                    TestImages.Jpeg.Issues.BadZigZagProgressive385,
+                    TestImages.Jpeg.Issues.NoEoiProgressive517,
+                    TestImages.Jpeg.Issues.BadRstProgressive518,
                 };
 
-            return TestEnvironment.RunsOnCI && !TestEnvironment.Is64BitProcess
-                                            && largeImagesToSkipOn32Bit.Contains(provider.SourceFileOrDescription);
+            return !TestEnvironment.Is64BitProcess && largeImagesToSkipOn32Bit.Contains(provider.SourceFileOrDescription);
         }
 
         public JpegDecoderTests(ITestOutputHelper output)
diff --git a/tests/ImageSharp.Tests/Image/ImageCloneTests.cs b/tests/ImageSharp.Tests/Image/ImageCloneTests.cs
index 82da5e2c4..82864f156 100644
--- a/tests/ImageSharp.Tests/Image/ImageCloneTests.cs
+++ b/tests/ImageSharp.Tests/Image/ImageCloneTests.cs
@@ -33,10 +33,7 @@ namespace SixLabors.ImageSharp.Tests
             }
         }
 
-        /// <summary>
-        /// https://github.com/SixLabors/ImageSharp/issues/576
-        /// </summary>
-        [Theory(Skip = "See https://github.com/SixLabors/ImageSharp/issues/576")]
+        [Theory]
         [WithTestPatternImages(9, 9, PixelTypes.Rgba32)]
         public void CloneAs_ToBgr24(TestImageProvider<Rgba32> provider)
         {
diff --git a/tests/ImageSharp.Tests/TestUtilities/ImageProviders/FileProvider.cs b/tests/ImageSharp.Tests/TestUtilities/ImageProviders/FileProvider.cs
index 2dbddcc8f..6475547a0 100644
--- a/tests/ImageSharp.Tests/TestUtilities/ImageProviders/FileProvider.cs
+++ b/tests/ImageSharp.Tests/TestUtilities/ImageProviders/FileProvider.cs
@@ -55,7 +55,7 @@ namespace SixLabors.ImageSharp.Tests
 
                 public bool Equals(Key other)
                 {
-                    if (ReferenceEquals(null, other)) return false;
+                    if (other is null) return false;
                     if (ReferenceEquals(this, other)) return true;
                     if (!this.commonValues.Equals(other.commonValues)) return false;
 
@@ -81,7 +81,7 @@ namespace SixLabors.ImageSharp.Tests
 
                 public override bool Equals(object obj)
                 {
-                    if (ReferenceEquals(null, obj)) return false;
+                    if (obj is null) return false;
                     if (ReferenceEquals(this, obj)) return true;
                     if (obj.GetType() != this.GetType()) return false;
                     return this.Equals((Key)obj);
@@ -133,15 +133,14 @@ namespace SixLabors.ImageSharp.Tests
             {
                 Guard.NotNull(decoder, nameof(decoder));
 
-                Key key = new Key(this.PixelType, this.FilePath, decoder);
+                if (!TestEnvironment.Is64BitProcess)
+                {
+                    return LoadImage(decoder);
+                }
 
-                Image<TPixel> cachedImage = cache.GetOrAdd(
-                    key,
-                    fn =>
-                        {
-                            var testFile = TestFile.Create(this.FilePath);
-                            return Image.Load<TPixel>(this.Configuration, testFile.Bytes, decoder);
-                        });
+                var key = new Key(this.PixelType, this.FilePath, decoder);
+
+                Image<TPixel> cachedImage = cache.GetOrAdd(key, fn => { return LoadImage(decoder); });
 
                 return cachedImage.Clone();
             }
@@ -158,6 +157,12 @@ namespace SixLabors.ImageSharp.Tests
                 base.Serialize(info);
                 info.AddValue("path", this.FilePath);
             }
+
+            private Image<TPixel> LoadImage(IImageDecoder decoder)
+            {
+                var testFile = TestFile.Create(this.FilePath);
+                return Image.Load<TPixel>(this.Configuration, testFile.Bytes, decoder);
+            }
         }
 
         public static string GetFilePathOrNull(ITestImageProvider provider)
diff --git a/tests/ImageSharp.Tests/TestUtilities/Tests/TestImageProviderTests.cs b/tests/ImageSharp.Tests/TestUtilities/Tests/TestImageProviderTests.cs
index 494c56dea..c5d9a7248 100644
--- a/tests/ImageSharp.Tests/TestUtilities/Tests/TestImageProviderTests.cs
+++ b/tests/ImageSharp.Tests/TestUtilities/Tests/TestImageProviderTests.cs
@@ -121,6 +121,12 @@ namespace SixLabors.ImageSharp.Tests
         public void GetImage_WithCustomParameterlessDecoder_ShouldUtilizeCache<TPixel>(TestImageProvider<TPixel> provider)
             where TPixel : struct, IPixel<TPixel>
         {
+            if (!TestEnvironment.Is64BitProcess)
+            {
+                // We don't cache with the 32 bit build.
+                return;
+            }
+
             Assert.NotNull(provider.Utility.SourceFileOrDescription);
 
             TestDecoder.DoTestThreadSafe(() =>
@@ -179,6 +185,12 @@ namespace SixLabors.ImageSharp.Tests
         public void GetImage_WithCustomParametricDecoder_ShouldUtilizeCache_WhenParametersAreEqual<TPixel>(TestImageProvider<TPixel> provider)
             where TPixel : struct, IPixel<TPixel>
         {
+            if (!TestEnvironment.Is64BitProcess)
+            {
+                // We don't cache with the 32 bit build.
+                return;
+            }
+
             Assert.NotNull(provider.Utility.SourceFileOrDescription);
 
             TestDecoderWithParameters.DoTestThreadSafe(() =>