so my future workaround will be, if I want to use the grid properly, i have to set up the first wall directly to 0/0 on the grid. so the first room can be attached to 0/0. like this:

from now on, every wall will be easier to read in the decimals.

hach, we Germans, everything has to be in order
thx for your time. I think I understand the reasons behind your explanation (snap to grid would be really annoying since too many options would appear)

thx!

I must not forget: very helpful programm!

PS: finally a working screenshot...