Halo 3 MCC: System.OverflowException Following Patch Creation Attempt

[ThisUsernameTextboxDoesNotHaveEnoughSpa]

Describe the bug
Encounter "System.OverflowException: Array dimensions exceed supported range" error upon attempting to create a Patch for Halo 3 MCC. This results in no patch file being created.

Halo 3 MCC: Sierra 117

1. Launch Assembly
2. Open Map Patcher
3. Load unmodified map from "...halo3\maps\010_jungle.map"
4. Load modified map of 010_jungle.map
5. Designate Output Patch
6. Complete Patch Details
7. Create Assembly Patch
8. Encounter:

`System.OverflowException: Array dimensions exceeded supported range.

at Blamite.IO.EndianReader.ReadBlock(Int32 size)

at Blamite.Patching.DataComparer.CompareData(IReader originalReader, UInt32 originalOffset, UInt32 originalSize, IReader newReader, UInt32 newOffset, UInt32 newSize, Boolean extraDataAtEnd)

at Blamite.Patching.SegmentComparer.CompareSegments(IEnumerable1 originalSegments, IReader originalReader, IEnumerable1 newSegments, IReader newReader)

at Blamite.Patching.PatchBuilder.BuildPatch(ICacheFile originalFile, IReader originalReader, ICacheFile newFile, IReader newReader, Patch output)

at Assembly.Metro.Controls.PageTemplates.PatchControl.btnCreatePatch_Click(Object sender, RoutedEventArgs e)`

Expected behavior
Click "Create Assembly Patch," successfully generate .asmp file.

PC (please complete the following information):

• OS: Win10 22H2; 14 October 2025 Patch

Additional context
Whenever attempting to generate patches for Halo 3, I encounter the same "System.OverflowException: Array Dimensions..." error at the same locations with every .map file. Each .map in Halo 3 has been re-installed and new patches attempted with various modified maps, but to the same error. When creating patches for Halo: Reach and Halo 3: ODST, I do not encounter this error.

[Lord-Zedd]

This doesn't appear to be a general issue with making patches, so I'd need more info on the modifications being made to the maps to properly debug this.

[ThisUsernameTextboxDoesNotHaveEnoughSpa]

Changes to Scenario, Character, Model, and Global tags regarding additional AI spawning and updated AI behavior. Trying to create a campaign similar to the Halo 3 XL and Mythic Campaign mods. I have attempted creating patches for the maps in each mod, as well, and have been unsuccessful.

[Lord-Zedd]

Is the modified file from the same build version as the unmodified one?
If they are the same, would it be possible to upload one of the maps somewhere?