Alt tab and disappearing base contents

Not the best title, but:

I was in the base layout.

Alt-tabbed out and went back in. The little boxes that show the bases and the buildings within (i.e. little green boxes or space) are there for the base that I was in but for the other had disappeared. These are the ones that run across the top of the display.

As someone else has mentioned a graphics problem with alt-tab, it might be that this is part of a larger problem as on its own it is pretty insignificant.

Using Win 7 and graphics card is an NVidia GT555M with up to date drivers (did em a week or so ago) and has enough memory (I say that because I've just read a review that says it's good with high-ish end games and I still don't know how much memory it gives me unless it's the high number I ignored in dxdiag because I thought it would be about 256 - 512 mb). Processor's an I-7.

The alt-tabbed vanishing squares at the top are a long standing issue. Really long standing. Probably won't be looked at until the new UI is put in.