Paint Shop Pro Photo XI

When I ran Windows 7 Upgrade Advisor on my XP machine it reported that PSP XI was compatible to run on Win 7 (64). I have installed it and just to be safe I changed the compatibility to XP SP3. On loading the program Windows reports that it doesn't like the colour scheme and has changed it to Windows 7 Basic but changes it back to Aero when PSP closes. From what I can see the program is not affected but apparently the desktop background changes.

Being totally ignorant of Win 7 and it's ramifications, can anyone tell me whether I will be doing harm to run this old program or is nothing being done to Windows itself. This is important because I had purchased PSP X3 (said to be fully compatible) but although it ran without any apparent clashes it was unable to see my Canonscan scanner. Corel politely told me that they no longer support this old version so I had to change back to my old friend.

All advice welcomed.

Canonscan 8800F. All the options under Import are greyed out an inacceassible.

It might be of interest that Fasstone Image Viewer sees the scanner and scans beautifully.

No, it is not relevant. I have subsequently managed to install my old Paint Shop Pro Photo XI and it scans normally, as does Faststone Image Viewer. I can also scan and copy manually uising the Canon ScanGear software. The problem is NOT with the scanner.