TBD (am I abbreviating that right?): I don't think so, While I don't want to say that for sure yet until I've made one or two more tests, it seems unlikely, since trigger crates can only turn triggers on, and if the trigger is already on, they don't turn it on again, they just have no effect. (Yes, the difference is observable.)

Stijn: I'd been holding off on that because I assumed it would just crash, but I tried it just for you, and JJ2 crashed as quickly as it possibly could.

Foly: To the extent that you need anything specific, it would definitely be the required functions. But I guess that's not really a helpful reply. For any more systematic editing of .j2l et. al files, you'll want to be able to read and write files (including ascii values, not just plain text), use zlib compression and decompression, and calculate CRC32 checksums. Occasionally you'll need to understand bitwise operations, but only rarely. Everything else is just basic programming. What I'm doing here, though, just changing individual values in data1, requires no more than a hex editor and j2ff, which hopefully Overlord doesn't mind me sharing the link to. (Only seems to work for 1.23 levels.) Animated tiles aren't documented anywhere, but they have a pretty simple storage format and begin at offset 15988 in data1.