Vanishing buildings

[Beeg]

It must be my PC but it's bizarre that it only affects that one feature. I've been playing SP since it's inception and haven't seen it before but I did upgrade my PC a few months ago. Any thoughts on what the cause might be?

I also have a graphics hiccup when I play scenario 12 (Operation Jupiter)... I get grass hexes popping up over the regular hexes on the left side of the map during game play. They go away when I hit the 'clear' key but come back when the game resumes. As I recall, I may have seen that in other scenarios as well (maybe it's the older ones).