Registering screensavers

I have to set a screensaver made by myself as the active screensaver from a configuration tool. I wrote from my program in System.ini - section boot at scrsaver.exe the name of the screensaver and it worked very well. After I've instaled an McAfee VirusScan that have some kind of tricky program that scans the disk while the screensaver is working, my configuration tool for the screensaver doesn't work well anymore. I presume that the information about the active screensaver must be saved in a diffrent mode but I don't know how.