MapEditor: Adding new map animations does not save correctly

[TiMMyyMMiT]

[TiMMyyMMiT]

NOTE: Data is saving correctly.

I have asked the community about this https://discord.com/channels/536315672083562508/536318731844845589/1492802997577584762
It seems that the "Tile Length" (Tileset Length) is the culprit but that this might be an engine issue - animation tilesets may be required to be smaller than map tilesets.