Hi Steven, thanks for the reply. I'm talking about the panel labelled "Track Information", in my case at the bottom of the player.
I'm afraid I can't find any way to customize the artist pics part of this panel, maybe I missed it (there are a lot of lil control panels in MB!). Meaning, for example, I'm not able to find any option to disable downloading artist pics into this panel.
Is it correct that MB is still looking in the "Artist Pics" subfolder for local images?
Also don't see options to modify the picture treatment in any way - eg, stretch/scale/crop etc. Not sure if that exists, as requested by the OP.