You may remember a few years back EA said it would no longer support all disk installations. I think you should check with @igazor because I think at that point mixed disk and digital download installations via Origin became redundant. I wonder if you have accidentally updated to v 1.69 because Origin will try to force that version on you.
As for using specific EPs or SPs you can use the filter in build/buy mode or uninstall the packs you don't want. No doubt you could try using DCCaches with different packs installed but that seems unnecessarily complex to me.
Finally I'm sorry you are still having problems. I expect you have already tried uninstalling and reinstalling CAW. The TS3 website can be very temperamental and a fresh download might be the solution.