Ok, if its using the right data layer I suspect  a data problem. Check the mp_Sites table and mp_Pages table and make sure they are populated. There should be 1 row in mp_Sites and several rows in mp_Pages.

The error makes me think its not creating a SiteSettings object which is what the MasterPages uses to know what skin to use. The missing data is the most likely cause.

The data looks right so my next line of thinking is whether the user can connect from the host. MySQL is very granular about who can connect and from what machine. If the db is on the same server as the web try using root with a blank password in the connection string. If not on the same machine, do you have a MySQL client on a remote machine that you can use to try and connect from using the mojo user?

Also make sure MySQL is configured to accept tcp/ip connections, you may need to refer to the MySQL documentation for that.

Other than that I can say I have never tested with mono 1.0.6, my understanding is the 1.1.4 branch is now considered the most stable. You might try deploying  the release files instead of the compiled sources and see if that makes any difference, though it really shouldn't. If you continue getting errors is it possible for you to un-install mono and install the 1.1.4 branch?

I try to be responsive on support, whether I can actualy help you is yet to be seen

Another possible culprit is the version of MySQL. Seems like I read about some issues with the ByteFX provider and a specific version of MySQL maybe 4.1.8

Do you have  machine where you could install a newer version of MySQL and give that a try? Maybe install it on your windows machine and then try to hit it from the Fedora web server.

I'll keep pondering on my end and post back if I think of anything else.