Just today I've been experiencing command line lockups. With several different commands (e.g., Extend, List, Erase, others...) I'll get to the point where I've selected entities, and get the prompt "Select entities:" again. Usually if I hit <enter> at this point, Intellicad performs the operation. But every 1/2 hour or so, <enter> does nothing. In other words, the "Select entities" prompt remains on the screen and the command does not execute. I can hit "escape" and get back to the main command prompt, but another try at using the command gets the same lockup condition.
If I exit Carlson and re-start, things work properly again.
Anybody have a clue? Thanks if you do!