Hello,
Sorry to hear you are having issues. Need to know if "Winter Snow" included in previous version of Deskscapes? If so, which Deskscapes version does include it. BTW, do know that Deskscapes 11 come with Effects features that you can apply onto any background. So that by itself could possibly do what you're trying to do. Something like screenshot below.

And there also DreamMaker Pro where you can create your own dream.

Thank you.
Basj,
Stardock Community Assistant.

If you have a backup of your Public Documents folder while the dream was installed you can pull the dream from there.

Excellent.     Keep copies of your pet dreams stashed away somewhere, sometimes they do come and go.