Tested Sweet Home 3D 4.1 as a new install on Win XP SP3 and it works perfectly.
Only thing to report is that any of the three sky images which come with the program for use in 3d view do not render in photo but that's insignificant.
I was still using v. 3.5 but will now replace it with 4.1
Many thanks for all the improvements made since 3.5
