Slitherine

I started to create a new scenario. The map is nearly finished, units for side 1 added. Suddenly when I added a sub leader to a BG and renamed it the mouse pointer went to the upper left corner of the map. No way to select one of the already placed units, the mouse pointer will always go back to the upper left corner. Any ideas how to solve this problem? Thanks in advance!

Well, just opened the scenario again and was able to continue the work.