[paint.net 4.0 alpha build 5034]

Ok. Looks like a translation bug. Try switching the language to English from the Settings dialog. I'll file a bug, of course. Thanks!

 

Yes, with English language it works.

[paint.net 4.0 alpha build 5034]

Crashes on selection, even on empty default document.
Open Paint.Net, press S, press left mouse button, move mouse - crashes. If lmb is pressed and released without moving, does not crash.
 

Crashlog: pdncrash.1.zip

English translation of the exception is "Input string was not in a correct format"

 

Windows 8 Pro x64, Russian, fully updated.