I was going to submit a PR, using the IMC fix mentioned here in the same vein as the Chisel compatibility code you've already got, but I'm not familiar with forge, and couldn't seem to get it working. Hardwiring BlockXtone#isFullBlock to always return true lets C&B recognize the blocks as modifiable, since that's what it's actually checking, but I'm not sure that that really counts as a solution...

Reopening until there is an actual release with this fix in it. Hopefully, it'll be available soon.

Fixed in 1.1.0