Church wall and corner don't align correctly

[Groundunit]

I'm putting together some walls for a little project I'm doing and I noticed with both of the walls "church_window_green" and "church_window_no_window" don't align correctly with "church_window_green_corner_concave_large". Before I start with a smaller snap sep. are there any other way of aligning it correctly?

[Vradcly]

make really small adjustments in position and size until its ok, then if ok is not good enough place a pillar or something similar to cover up the error .

[Acies]

Turn off grid snapping - then it should be easy. Do it by clicking "the magnet" in the bottom left corner. This will allow you to adjust walls, entities etc. with more precision.