Scratch that, I apparently hadn't rebooted, downgrading to 2.3.3 was only a temporary fix.
I've gone through and completely wiped btsync from my system, re-installed 2.3.0, and reconfigured everything. It seems to be working now (have rebooted once and everything was still properly working), but we'll see if that continues to be the case.
Again, won't be updating again without some clarification on what's going on here.
Also, I don't have a .sync folder in .btsync. I have several .SyncUser folders, however. Not sure why there are multiple, or how those folders are getting generated though.