Icon Developer run with no issue on my Windows 10 system.
You could refer to this thread as a reference : https://forums.stardock.com/485907
Stardock Community Assistant.
I was actually just about to ask the same question as the OP did. You might inform the Stardock Team that is in charge of the website to go through and update some things and also those that programming the Object Desktop app.
Like with this program, the Icon Developer. Here it was it says on the website and in the Object Desktop app. And I'm on the latest version of Win10, probably same as you are on.
As I mentioned in another thread, it's not good advertising for you as a company if customers are looking for Software and then see it is for WIndows 7 (or in some cases, even saying for Vista and XP). Some Customers just reads the description of the products, see it is for an old windows OS and then move on.
Just my two cents.