Had a weird world gen happen, ended up with 2 structures on top of eachother.

This was running on the RR3 pack with most things on, and using Realistic World Gen world type.
(not sure if the worldgen has anything to do with it per say tho)

Thanks for reporting. While very rare, this was bound to happen in 0.9.5 and earlier. This is actively being prevented with 4b66fc0 - or in other words, the 0.9.5.1 release :)