[Gtkradiant] [Bug 962] Installing 1.4.0-RC2 and then uninstalling 1.3.13 messes with 1.4.0

[gtkradiant@zerowing.idsoftware.com]

http://zerowing.idsoftware.com/bugzilla/show_bug.cgi?id=962





------- Additional Comments From wjoseph@europe.ea.com  2003-12-17 03:54 -------
The installshield setup uses the registry to store refcounts for files.. but 
that's not the problem.
I suspect that the uninstall is removing stuff in quake3/baseq3/ that was added 
by another installation - removing mapmedia.pk3 is pretty much guaranteed to 
break the other installation. This can be solved by telling IS to treat those 
files as "shared" - so it will add a refcount for those files to the registry, 
and won't uninstall them unless their refcount is zero.