Have a look at
http://svnbook.red-bean.com/en/1.7/svn.serverconfig.pathbasedauthz.html.
If you are in need of a conditional commit access control mechanism, you
should consider using a start-commit hook - see
http://svnbook.red-bean.com/en/1.7/svn.ref.reposhooks.start-commit.html for
details.
Be
No chance for that, sorry.
Anyway, version information should rather be stored within the resource
area of the PE file instead of abusing the time stamp for this purpose
(provided that you are really talking about Windows, as the term
"EXE-Files" implies).
Perhaps you might ask them to use the VER