Sync to characters corrupted
Freeze button has no effect
I can confirm this is fixed in 3.0.1.44.
Disabling the send functionality would be the most user friendly solution (maybe with a status string "port closed" withing the send data area) as it gives the user feedback even before s/he performs a useless action.
Highlighting of sync string corrupted when "lazy"=off
Access violation when sending sth on closed port
Same issue here, Win7-x64 SP1 German.