I finally got mine fixed. Now the new WB5 beta released on the 2nd works fine. Here's what I did, maybe it'll help you too.
Completely uninstall all Stardock products and reboot. Then delete the entire Stardock folder under Program Files if there is anything left. Afterwards, open regedit and search for every single instance of Stardock, Object Desktop, and WindowBlinds that you can find, and delete every single one of them.
I did that, and then reinstalled SDCentral, updated it, rebooted, installed WB5, rebooted again, and it worked . My guess is there was something getting left in my registry that was preventing any version of WB from working, because I had also tried the uninstall SDCentral approach before, but it wasn't until I cleaned out my registry by hand that it started working again.