I've noticed that when I right click on an image in explorer, I get the option to set it as desktop background. But this doesn't appear when I right click on a image browsed through TLB
It would be nice to have the option.
Please can you post the screenshots with explorer and TLB context menus.
Are you talking about internet explorer? I can't get "Set as background in Windows Eplorer. Yes, please post some screenshots.
As far as I know, I have no spetial progam installed to get that option on the explorer menu
Try to turn on the option:
TLB Settings->Context menu->Show full shell menu