Problems with panning and clip in GEM

[sgz]

I've suddenly become unable to pan around maps in the GEM editor. Moving mouse arrow to edge of map just makes it become a red X. Still able to rotate and zoom but only way to move map view is by clicking on the minimap. Any tips ??????????

Also the coloured "clip lines" at edge of map will now not go invisible - even when playing a mission in the editor. This was never the case before. Help ..........