When I received a chat while playing I was alt-tabbed out. Upon trying to alt tab back I just had a black screen with the music playing.

Tried to alt-tab to browser but wouldnt work, stays black. Start bar showed up though and highlighting browser with win7 preview showed the window until I clicked to focused where it went back to black.

Only solution was ctrl-atl-del to bring up task manger which stayed on top of black. Killed process from there.

Win7 x64

Geforce 9600M GT

Macbook Pro 4GB with T9600 Core2Duo 2.8Ghz

I have encountered this as well but mostly I only see a black screen as mentioned in another BUG post.

blank screen on return from alt-tab

windows XP 32 bit, pro

AMD processor (dual core)

GeForce 8800 GTS

Is this what you are talking about? That is what happens when I alt-tab. That is all the way zoomed out btw.

Same thing happens when I save a game and exit....when I later reload the saved game, all the map textures (including cities/borders) are gone, I can only see units....

For version 0.24 (Beta 1A), the alt-tabbing works a bit better, but many map features are still missing.

A before and after:

Goodies, forests, cities, mountains seem to have disappeared, while the map itself, the rivers, the sovereign and city name are still there. It's not in this shot, but I also noticed that the outline around the ocean edges was also missing on coming back from alt-tab. 

debug.err