Just switched to the experimental build (from 0.17.79 I think) and updated mods, and I'm getting a non-recoverable error:

Error while running event crafting_combinator::on_load()
crafting_combinator/script/signals.lua:47: attempt to index field 'signals' (a nil value)
stack traceback:
crafting_combinator/script/signals.lua:47: in function 'on_load'
crafting_combinator/control.lua:28: in function <crafting_combinator/control.lua:23>

Sounds like the same problem as this. As I said there, this is a case of migration being broken. It's not really worth fixing though, as there have been significant changes in the mod between the last 0.17 version and now, which I can't really make any meaningful migration for.

Your best bet in this situation is to either save without the mod and then install the new version, which is safe but deletes any combinators you have. If you want to keep the existing combinators, you can try installing version 0.14.0 as that was the last one before the big changes and should be compatible with the 0.17 versions.