Форуми / 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:

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

Thanks for the command but it did not fix it, this is really weird. I still need to remove the slimbox folder to get my site working again.
So, I disabled AJAX (in main config), that fixes it and the error is gone (but what if I want to use AJAX?). So I figured, if I disable AJAX I can maybe install it, but that too does not work as I now get a fatal error upon slimbox plugin installation: 

I tried the change you suggest above but it ends with the same fatal error.

[update]
If I run the SQL command after disabling AJAX and after succesfull uninstall of the plugin I enable AJAX the error is gone. That might have to do with your above fix, but not sure about that.
The only thing I am sure of is that this plugin does no longer work

Plugin should now work on Siena.

http://www.cotonti.com/extensions/files-media/slimbox_siena