hI Amie,
You check if you have SQL on cluster, if so then try to provide the cluster name while running MDB installation. you may open the temp file of logged in user to review install_mdb.log file to check what errors are recorded.
The alternative approach is to run from the command line utility which was posted in previous thread.
Normally the error seen is related to access to the database server, and not that the MS-SQL server version is not supported. The user logged in the database server should be granted trusted connection to the sql server.
For example, try to log into the database MS-SQL server in SQL Server Managemnet Studio selecting "Windows Authentication" as the Authentication type. It should be able to connect. And beside the trusted authentication this logged in user should be sysadmin to the SQL server.
~vinod