The file named Registry.dat is used for Registry redirection. runs in a special environment where any accesses that the app makes to the file system and to the Registry are redirected. Apps from the Store can't mess up your system on a global scale. This is one of the main benefits of the Windows Store. Here's some of the details about what's happening with your app behind the scenes, from this article.

Apps that live there are safe, won't mess up your machine, and are quickly installed and uninstalled. It lets you basically put any Windows App in the Windows Store, which is cool. This was called 'Project Centennial' when they announced it at the BUILD conference. The Windows Store is starting (slowly) to roll out and include existing desktop apps and games by building and packaging those apps using the Universal Windows Platform. Now that the Evernote app is a store app it can use Windows 10 specific features like Live Tiles and Notifications and it'll be always up to date. NET apps and just like UWP (Universal Windows Platform) apps, so I found this to be pretty cool. But it's a Windows app, just like VB6 apps and just like. It's a Win32 app and it appears to use NodeWebKit for part of it's UI. No nextnextnextfinish-style install, it just worked and it worked nicely. I went to the store, installed Evernote, and it ran. I noticed today that Evernote was in the Windows Store.

Vb6 installer