Check file, try subselect top and move up with gumball.
Rhino needs to recognize situations that doesn’t work with move face AND report messups like this.
Maybe it’s a self fulfilling prophecy… If nobody uses it, it is no need to fix it, and if you don’t fix it nobody will use it…
I really hope facemanipulation can get some real love in V8.
Both the distoriting tool that we have now, and a new one where the surrounding surfaces are kept intact and just extended when needed. (Like spaceclaim does) I often need to rotate a face a bit, but that just messes everything up in Rhino.