Oh, right, Ctrl+C is the default console hotkey. Yeah. If you select the building in design mode, and run ib, you should be able to insta-build it. But this is debugging functionality, so things may break and your save might end up in a weird state.
-unless both you and the host have the exact same template- /temporary workaround.
(as in player designs made in single player, saved, give file to the host when playing multi, then both you and the host can use that file, and hearthlings do all the correct stuff)
if you design something, the hosts click it and saves it, and you do too, you might actually be able to do it right there and then, but i have not tested that exact situation.
check out my pic in the other thread about the workaround.