I hope this issue because of display problem. Try to change your display and see. I have faced the same problem with some Hole features, what I did is I switched off the preview option. But in GD&T case , we can't turnoff the display.
Is the GD&T symbolembedded in a note.WF 2.0 has a bug with embedded GD&T symbols. A crash will occur if you attempt to modify the note. If you have a note with an embedded GD&T symbol, modify the GD&T symbol from within Prt Model or Assembly Model.