So, because Fpcupdeluxe failed to install OPM, probably because it is supposed to be part of Lazarus, I just issued a svn checkout in lazarus/components ..
I opened the package, compiled it, and opened the package install dialog and installed it. Rebuilt Lazarus..
And it is installed!
Settings seems to be alright.
I haven't tried to install anything yet.
Really nice!
Edit:
Castle Game Engine should be in it!