I looked though the rom years back. I don't really remember stuff in terms of offsets, but I do know that how the levels work is that layer 1 and 2 are treated as separate blocks of data, each with their own pointer. I think I also found the exits data too, but again, I don't remember any offsets. Maybe I will take a look and see if anything jogs my memory.
Edit: I found some notes I made. Apparently level data starts at 0x48000 in an unheadered rom(so if yours has a header, add 0x200). It looks like the format is one byte for each block. As for warp data, I have 0x!f400, but I forget if it's the start of the data or one of the rooms near the beginning of the game. I also forget the format but I imagine it must have a location on screen and the warp index the warp points to. Usually the format in room based games have a value for what room the warp appears in, it's position on screen(in this case might have a length and width value), and the warp index it points to.
That is all i have, and all that I've looked into. There is potential, and it's a shame that nobody has looked into this game much.