Thanks to everyone who pointed me towards SQL. The issue appears to be a failed or only partial install of the Microsoft SQL Server Compact Edition (v3.1, aka 2005). As you can see from my earlier attempts, I tried to load the latest version (v3.5) with no effect.
My steps for solving were:
1) Uninstall Centrafuse
2) Uninstall all versions of Microsoft SQL Server Compact Edition
3) Restart
4) Install Microsoft SQL Server Compact Edition v3.1 (aka 2005) from this link:
http://download.microsoft.com/downlo...verCE31-EN.msi
5) Install Centrafuse
6) Rebuild library.
There are a few other things. At one point, I added the SQL Server path to my PATH environment. I have not deleted it, so I'm not sure if it is needed or not. No one else has seemed to need this, so it's not likely to be necessary.
Also, SQL Server Compact Edition v3.5 IS NOT A SUBSTITUTE. Installing it is ignored by Centrafuse. You need to have v3.1.
George