Try pressing the 'r' key instead, or you could try to reinstall studio. I've never had this error before so I don't have the experience on how to fix it.
Also the map itself may be glitched. Try to make a new map and then see if the refresh button works then. If it does, then your terrain.blk may have an error and you might need to restart your map, or make the minimap from scratch.
I may not make the best maps, or be the best player, but I put a lot of time, effort, and care into my stuff. That counts for something, right? No. "Can we order a pizza?"
GameRanger ID: 913974