The map set that someone uplaoded to my guild's forums used a lot of _1's and _2's (the layering used in-game).
Not knowing the contents of these yet, I took only the _1's and converted them to SEQ format:
http://misc.llaffer.com/sod_seq.zip
If it turns out the _2 data would also make sense to be added to seq, then I'll re-work these files. But for now, this is what I have.
Enjoy.