Being able to specify floor styles would be amazingly handy, and shouldn't be too much extra I would think?
Basically, using A, B or C (Z for stairs down)for example, I could have
AAAA C BBB
AZZA C BBB
and so on and so forth. Also useful for stairs and other things you want to be specifically placed floor types.
If it ignores everything it doesn't recognize that would be good, then symbols could be replaced to do much of that, but definable floors would be a big plus.
Also, I wonder about the size of the map, mine is growing above 200mb already... But it looks great, and has sped up my construction process by a long way, even if I do have to strip out all the pretty floor tiles and replace them with a few background drawings, it will still be an improvement, so thanks a lot for that!
I'll send you the excel files later tomorrow, probably, and now -I- sleep... far, far later than I should.