[2020] Building became impossible

Hi @liquidand, were you using only square foundations or also triangular ones?

Was there any ceiling present, or surrounding pillars?
If so, it might be best to temporarily remove thesefor the sake of placing down large structures.

We’d also suggest that you try using the raise/lower option to adjust the large placeable, as well as trying to tilt it slightly, as this usually helps finding a snapping point.