Building newbie may have doomed phase.

[Building newbie may have doomed phase.]

The issue has been resolved and I am in awe of this a great community.

[Building newbie may have doomed phase.]

Hey, I'm building my first phase and having a great time with it, unfortunately, I seem to have discovered an issue. In trying to quarter an area off, I spawned a wall that I intended to shrink and fit in place, but as soon as I use the command gob select, an error window appears and crashes my game.  Subsequent attempts result in the same issue and now I have a over-sized wall cluttering my phase I was so proud of building.  I would be grateful for any assistance.