My game hangs whenever I enter the Nether using the Void worldtype. Using the SINGLE_GRASS structure that comes with the mod, with version 6.1.0.24 for Minecraft 1.10.2.

I am unable to reproduce this, what do you mean by 'hangs'? Do you have a log, and a world save?

Sorry, just found out it was caused by Natura messing up void worlds and not this mod.

I would like to request the ability to choose which dimensions are void via a config of some kind though. For the pack I'm working on I'd like to be able to force the nether to generate as a void, but I want the overworld to be an endless ocean. As far as I can tell there's no way to do that with YUNoMakeGoodMap?

As it sits no, ive been trying to think of how to allow for customization of the terrain gen.
I'l like to have things like the platform selection, but for world type.
Like being able to select:
'void' which would be now
'ocean' 1 block bedrock, ~5 blocks sand, 250 blocks water
'desert' 1 block bedrock, ~60 blocks sand
and more

Just haven't gotten the time to re-work the mod to be like that, and the customize screen is really annoying to make...

The superflat and customized world types in vanilla are pretty good for stuff like that (I'm using customized to make an endless ocean world and it works great) but as far as I can tell there's no way to tweak anything but the overworld with them. I imagine having a config for which dimensions to void and a different platform for each dimension would cover 98% of use cases.