I puted displacement on my roof and got the problem because on in some places it’s positive (up) and in some it’s negative (down) what can I do to fix it? 
can you post the settings of the displacement map?
looks like you may have the map mirrored rather than tiled or possibly a problem with the uv mapping…
LOL lukasz, ask george. He is got a lot of free time now 
but to be honest thats the way i do it… i have MAT LIBRARY on my XEON there… just Instance DISP MOD with diffuse for christ sakes…
okey, now it’s working fine. Thanks
yo dood…may i welcome you to cyprus? are you here finally?