IMC 7.2 corrupt database after upgrade, how do I revert to 7.1?

[AlphaCen]

I have IMC 7.2 running Win 2008 Server R2 which has been recently upgraded from version 5.1 through all the recommended intermediate releases.

I currently have a problem where the IMC will not start.

One process imcnetresdm.exe has failed to start with the error message "Unknown error occurred in starting the process".

The error in the log for imcnetresdm says "a conflict has occurred in database 'config_db' table 'imc_config.tbl_dev_accesspara', column 'snmp_id'" and seems to be related to me trying to delete a device from the database.

imcvnmdm.exe process is stuck indefinitely in status "starting".

Unfortunately I only have the database backup taken before the upgrade from 7.1 to 7.2 .

Can you advise how to downgrade the Platform software and all components back to version 7.1 so that I can then restore the database from the version 7.1 backup taken just prior to the upgrade?   Do I have to undeploy all existing components using the Intelligent Deployment Monitoring Agent first, then use the same tool to install the version 7.1 platform and components?  Will the license be preserved?

Any help would be gratefully received, thank you.