ATG works fine when BOP is installed, but I rarely see BOP biomes, despite lots of exploration. So far, I've seen Woodland, Shrubland, and Gravel Beach biomes from BOP - otherwise, I've only seen vanilla biomes.

ATG does currently not have support for any modded biomes. The biomes mentioned is added by ATG.
TTFTCUTS is currently working on support for modded biomes though!

If you look at the recent commits, you can see that I'm in the middle of working on customisation and mod support. The three biomes you mentioned are added by ATG.

@TTFTCUTS Do you have any rough ETA? (I.e. more like weeks or more like months...)

It's not that I wanna rush you, it's just that BoP terraingen is really getting on my nerves. It can't seem to generate a world I like. :)

I honestly don't know. There's a lot to do, a lot to learn, and between working out how to do some things and finding the motivation to do so with other things eating away at my time, I couldn't possibly say right now.

@TTFTCUTS I think I know how you feel -- I hate estimating. I usually feel like I'm offering a time period that is too high, but if I say anything smaller, I feel like I might not meet it. Worse, no matter what my estimate turns out to be, it often takes me 1/3 the time (or less) or 3 times longer (or more)! Don't those people asking for estimates know that software development is an ART, not a science? With rare exception, nearly everything I do involves unknowns that take hours of research along with trial and error before I can finish the job.

@TTFTCUTS Fair enough. That tells me it will be at least long enough that I shouldn't postpone any other plans in order to wait for it. :)

(I would kick myself if I started a whole new playthrough and 2 weeks later it could have been 1000% more awesome.)