Fixed a crash when user cancels engine launch during Test Map action.

These changes were made in previous commit. I just forgot to write info about them:
Classic modes: going to Draw modes when Edit button is pressed when nothing is highlighted can be disabled in Preferences -> Editing -> "Start drawing when Edit pressed over empty space in Classic modes".
Classic modes: removed Preferences -> Editing -> "Try to align horizontal tex. offset of dragged geometry", because it was more confusing than helpful...