hi !
use the newest iris 2 sourcecode from svn, as it contains the latest bugfixes, available via
install subversion
svn co
svn://iris.schattenkind.net/iris/trunk iris
after reconfiguring libs/compile options and similar you better use
./makeclean.sh
just to make sure that everything is compiled fresh.
i'd suggest using the 32 bit fmod version even on a 64 bit system, might be worth a try.
also some people seem to have had problems with the newest ogre version under linux, i'm still using ogre 1.6.1 , compiled from source via
http://sourceforge.net/projects/ogre/fi ... 2/download
(see installdeps.ubuntu.sh for instructions on how to build)
if you still problems compiling please post the error output.