It works for me, upgrading from Windows 7 to Windows 10, but I tested fresh Deskscapes (all v8.21) installs on Windows 10 betas with only the same problems detailed below.
I don't use Task View, so I can't comment on that.
But the only bug I see regularly is a multimonitor assignment one.
Monitor layout (according to Windows ID in Windows 7 and 10, both x64).
3 1 2
According to Deskscapes the monitors were the same under Windows 7, but under Windows 10, they ID as...
1 3 2
Note that this is based on which Dream goes to which Monitor when selected. W10 still reports the 3 1 2 monitor IDs.
Now, this also causes a problem with the selection of Primary Monitor.
I normally have the middle monitor as Primary (for games, etc.). This caused no problems for Deskscapes under Windows 7.
Under Windows 10, I MUST have the leftmost monitor as the Primary or else Deskscapes PhotoDream will not work on the leftmost monitor (where I want it).
It appears to me that, under Windows 10, Deskscapes ALWAYS selects the Primary monitor as Monitor 1 no matter where it is, no matter what Windows 10 IDs it as. I assume this means that there is something different about how Windows 10 reports Monitor ID vs. Windows 7, of course.
Despite all of this, once I got things working, the really good news is that Deskscapes works FAR BETTER on Windows 10 than Windows 7!!!
For example, the Master Baron's gorgeous Goodnight Earth video dream used to microstutter under Windows 7. I don't know if this was a codec issue or an underlying "I'm pushing Windows 7 too damned hard, Captain" issue or a Deskscapes/DirectX issue, etc. But I know it wasn't a graphics driver issue because the same thing happened across different display cards and monitors/resolutions, But under Windows 10, Goodnight Earth is smooth as silk no matter what resolution I run it at, so I now suspect the problem was an underlying, core Windows 7 OS issue that Windows 10 resolved (perhaps as part of the move to DirectX 12?).
So, except for the things I had to work around, I've never had a better Uber-Deskscapes (re: 3 different dreams across 3 30" monitors) experience than I do with Windows 10. Once they get the bugs worked out (which I don't suspect will take them long), I think Deskscapes owners are going to be VERY happy with Windows 10.
I hope this helps someone somewhere someday.