Incorrect icon association in Win 7 64-bit

I have installed the 32-bit version of PhotoPaint X3 on my Win 7 64-bit machine, and, so far, it seems to be functioning OK.  It is only a minor niggle, but, although I have associated several bitmap formats, like .tif and .jpg both in PhotoPaint itself and in Default Programs/Associate a file type, in Explorer/List View only the generic icon is displayed (a plain white sheet of paper) rather than PP`s icon, even for .cpt extensions, although PP`s icon displays next to the "Open" button in the Explorer toolbar if I select an associated file format.  I have tried all manner of ways to rectify this, including rebuilding the IconCache.db, but without success.  Is this a 32-bit program versus a 64-bit O/S thing which I shall have to live with, or is there a way to get PP`s icon back where it belongs, please?

Thanks

Trik