identify the previous version installed from backup files

Could anyone provide a way to identify the previous version installed from backup files, eg reg entry for Enterprise, Express, etc
We've had a physical DC crash which had this running but have never had to deal with (inherited, appears to have been v3, v4 and currently 5.0.2)

Centrify Corporation Centrify Common Component 3.0.0.100        3.0.0.100       

Centrify Corporation Centrify Deployment Manager 2.1.2.443      2.1.2.443       

Centrify Corporation Centrify DirectControl ADUC Extension 5.0.2.388    5.0.2.388       

Centrify Corporation Centrify DirectControl ADUC Extension 5.0.2.388    5.0.2.388       

Centrify Corporation Centrify DirectControl Console 5.0.2.388   5.0.2.388       

Centrify Corporation Centrify DirectControl Console 5.0.2.388   5.0.2.388       

Centrify Corporation Centrify DirectControl Password Sync 5.0.2.388     5.0.2.388       

Centrify Corporation Centrify DirectControl Password Sync 5.0.2.388     5.0.2.388       

We have backups of the DC however the previous administrator has not kept the install files on the server.
I'm unsure what might happen if we just install the latest express version.

So if possible could also let me know what version of the suite I need to re-install the same version.

Any advice appreciated.

Thanks