why is the applied fill different on the different side of the slab and how can I align all of them?
both OpenGL textures and 3D window's hatching seems to get this problem when aligning texture's/fill's direction under Edit/Align 3D Texture command.
If you use the OpenGL settings and "reset" your 3D texture to default (under Edit/Align 3D texture and then instead rotate the texture (jpg) of your choice under Options/Material's menu it will work fine.