As far as I know, if you set Update (Basic) Program to Manual in 4.8 then only the Virus database will be automatically updated.
If you do decide to update to Version 5, then from my own experience (and despite the fact that V5 is supposed to be able to remove 4.8 automatically during the installation) first manually remove version 4.8 via the Control panel add/remove entry, reboot, cleanup with something like CCleaner and then reboot again before installing V5. Some advise to (also) use the Avast removal program, and that wouldn't hurt.
Once I had done this, V5 installed and functioned perfectly well on my PC. I do have Cyberlink Power DVD, Power Director and Power Producer on the PC, but none of them use the particular file that has been reported as causing a problem with V5, so I assume it depends what version of the Cyberlink software one is running.