The /etc/xdg/menus/hildon.menu file is about organization/hierarchy of the menus and placement of the icons, not about rotating and display orientation? Or is it?
Anyway, I tried again installing 0.7.3 (now from extras-testing) and the issue/bug I pointed out is easy to reproduce. However, after running /opt/catorise/catorise configure (which I had to do because several icons/apps seem not to be categorized as reported by qw3rty), the problem vanished. Given this, the root cause of this issue might be beyond the scope of Catorise.
Can you, Jaffa, by the way explain why you made the set of specific /usr/share/applications/hildon/catorise-*.desktop files?