Ok, maybe I’m just dense, but are we not allowed to place a template on top of another already built template? I was going to try my hand at a relatively quick Firefly Clan playthrough for the ACE contest and I “designed” a platform for my goblins to eventually build homes on top of rather than trying to build the whole damned thing in one go. Build platform here, build platform over there, good to go. Designed a one-goblin sized hut (9x9 blocks with walls I think?) and it fits relatively nicely on the platform good. Save as template and place the template right the-…wtf? Why can’t it go on the platform? I swirled my mouse all around and it just won’t “jump” up to the platform. It only wants to build it on land or in the swamp water. Did I miss something? Or will it literally only work if I build the platform and the hut all as one single template? And is there a way to combine two buildings into one template or would I need to completely rebuild the design?
I havent tried so im probably not going to be able to help you with this one atm 
that is not a bug, just how the editor works
you only need 1 connected block to touch the ground for it to work
you should be allowed to build buildings on top of other buildings, including platforms. but sometimes it can be a bit fussy on letting it place on it. im also not sure if you are allowed to place -templates- on top of other buildings. you are allowed to freehand build on top of the already built buildings though.