The SP4 is worse than SP2 or 3, I want to revert back to this without having to remove program completely. Is this possible?
Are you having issues with the server side of PDM SP4 or the client? You can use an older version of the client with the servers being on SP4. In order to move the servers or client back to SP2 or 3 you would have to uninstall then reinstall. Unless I am unaware of something, but as far as I know SP3 will detect that SP4 is newer and won't let you upgrade.
I would suggest to first uninstall SP4 from the client and install SP3 and see if you have the same issues.
That is correct. If you try to install SP3 with SP4 installed you get something like this.
Retrieving data ...