Forums / Cotonti / Extensions / Slimbox not compatible with Sienna 0.9.9?

I tried install the Slimbox plugin ( http://www.cotonti.com/extensions/files-media/slimbox_siena ) on a clean install of Sienna 0.9.9 but during install you get an error about an object ( this is the error: AJAX error: [object Object] )
However, the plugin installs half and stops your site from working (all pages show url not valid error).
You can not uninstall the plugin cause that same error pops up.
I pasued the plugin but that too does not help. Only thing that works is removing the slimbox folder from the plugin folder, than the site work again however an error still shows above the header:

Warning: include(plugins/slimbox/slimbox.php) [function.include]: failed to open stream: No such file or directory in /home/xxxxxxxxxx/public_html/testers/xxxxxxxxxx/system/header.php on line 92

Warning: include() [function.include]: Failed opening 'plugins/slimbox/slimbox.php' for inclusion (include_path='.:/usr/lib/php:/usr/local/lib/php') in /home/xxxxxxxxxx/public_html/testers/xxxxxxxxxx/system/header.php on line 92

I know there is an SQL command to run over the DB to uninstall plugins which cause issues however I can not find that anymore. I used the search as well as google to try and find it here on the site but it must be hidden deep in the forums.
If anyone knows how to fix this without me having to delete the DB I would be very thankfull