Side of print is influenced by other parts

I’m trying to print a fairly simple object. A box open at the top, with a window on the side.

As you can see there are several problems with the print. The first layer seems to have a “skirt” effect, and the surface of the side (which is closed) should be uniform, but it seems to be influenced by the other side where the window is, resulting in ridges where the window begins, and ends.

It also isn’t flat on the bottom, maybe because I used concentric pattern for the bottom layer.

My printer is a bambulab a1 mini, using bambu pla, 0.4 nozzle, 0.4 line width, 0.2 line height.

The object is 240mm wide, 240mm long and 360mm high.

It was printed by slowing down the printer to 50% speed (silent mode).

Any ideas how this could be fixed? This would be a modular lamp and it would only look nice if the surface is uniform.