While trying to install AFS ImageDepot Express for a user, I ran into some issues, namely the following error:

unable to configure local datasource

as well as a problem with "exclusive access to file" when trying to change the datasource in the program. Turns out that by giving the user Modify permissions on the Program FilesAFS folder and giving them Modify privileges to the registry key HKLMSoftwareODBC (and sub-keys, especially ODBC.iniAFS) the problem is solved.