I'm trying to install the new version over the existing one without de-installing the old one. At the wizard, when choosing the destination folder, I get the message I have no write access to the folder. I'm going to have a look at this for now myself, but waiting 7 hours is way too long for yEd; perhaps you're encountering something likewise (no permissions; no access)?
I'd say abort the installation and try again. Maybe you get more information from Window's Administrative tools? (to be found in the configuration panel)
