Receipts not writing, some applications not installing properly

Hello --

I have a new MacBook with Leopard pre-installed. I've been trying to install some Safari plugins and other applications. The applications are mostly installing fine, but the Safari plugins have had real problems.

I ran the installer for SIMBL and for two plugins (ForgetMeNot and Inquisitor) several times, and they never appeared to install, though the installer program said it had done everything it needed to. It turned out the program never created the folders in my Library that it should have (Input Managers, in the Library, and SIMBL, in Application support). More disconcertingly, none of the software I installed has left a package receipt -- there isn't even a receipts folder in my Library.

My wife also recently got a new MacBook with Leopard installed, and she hasn't had any similar issues.

I've repaired permissions and zapped the PRAM, but I'm thinking it's time to archive and re-install Leopard. Since that could take a while, I'd prefer not to if there's another solution. Any help would be much appreciated. Thanks.

Mike