Well, somehow I managed to break something since the numbers when building or selling have disappeared for me. The fog around graveyards and the portal has thinned significantly and the small "flames" around your rooms have almost vanished.

What have I done? Did I by accident hit a graphics hotkey? Have searched around in configs and on this forum but haven't been able to solve the issue. It's not gamebreaking but annoying as hell.

EDIT: Loaded a different map and the text is there...so I guess this is a non issue but i'm curious, did I hit some sort of cap? Haven't played the map very long, although there is 3 computer opponents, so I don't think i've hit any of the object caps.

Bingo.

The amount of things is limited. When you reach the limit, the game starts freeing unnecessary things to fit more important ones, and creation of most effect things fails.

It is clearly visible during fights - when the limit is reached, creatures can no longer shoot spells.

You may play a little longer by selling large Workshop, Training Room or Treasury. Other than that, the only option is to restart the level.