I found this thread while searching for my own solution to this problem. Your video shows what I first tried three weeks ago.
In Windowblinds 6.1 on my XP machine, there was a check box to turn OFF blur. I hate blur. "Never blur the background even if the skin has blur enabled" God I miss version 6.1
It looks like in the new version, someone really enjoys blur and thinks that the rest of us do too.
Now on my Windows 7 notebook, 6.1 will not install. It's a shame I have to buy something I already have, but that's the nature of software I guess. I'm using the trial period of WB7 right now... However, by your own video's example, blur can be turned down but it cannot be turned OFF. Gone. Hence, the wording, "Clear as Glass" for this thread.
I am unwilling to buy WB7 if I can't turn off the blur. For me that is the most important function. My favorite theme is Diamond but I have tried others. Get rid of the blur completely and I'll continue to be a customer.
Sorry, but I'm mildly peeved at this situation and even more peeved at your posting that it will work when it obviously doesn't and all I have to do is throw money at it.