ATIH v11 incompatible with DiscWizard

I am still running Win XP home (32bit) SP3 on my home desktop PC. I also have been using successfully ATIH v11 for backups. I bought some Seagate 3TB hard disks having read that Seagate DiscWizard would allow me to use the extended capacity (beyond 2TB) in WinXP. After installing & using Seagate DiscWizard (evidently by Acronis) and successfully setting up my 3TB disks as a 2TB disk + a 1TB partition, I discovered that when I tried to launch ATIH v11 it fails with the message "Acronis True Image Home can not find the proper serial number. You should reinstall the product". I had seen on an Acronis forum thread where this happened to someone and Acronis said you can only have one installed at a time (since both are actually from Acronis).

My concern is that if I reinstall ATIH v11 then I will no longer be able to access the extended capacity on my 3TB drives. If I don't install ATIH v11 then I loose the extra features of "File backups", "Try & Decide", etc that I don't have in the version of DiscWizard that I downloaded from Seagate web site. I'm hoping that I don't have to choose between these 2 things, but can have ATIH v11 back and continue to access the extended capacity of my Seagate 3TB drives I just purchased. The DiscWizard manual says:
While uninstalling the product, you will be asked whether you want Extended Capacity discs to be removed also.
- If you decide to remove them, Windows will still recognize a disc size correctly while Acronis driver is still installed in the system;
- If you decide not to remove Extended Capacity Discs, they will remain accessible for Add New Disc and disc management tools while Acronis driver is installed in the system.
I’m not sure if this is related to my concern.

I also own ATIH v2010 but when I had tried to install it on my WinXP desktop PC it would often go to blue screen (not sure why: 2TB drive on USB, or what) so I stuck with ATIH v11.

Please help!