With the help from RonGeorge I got som STL that was complex and crashed Windows File Explorer.
After some testing I was able to get all file rendered to thumbnails.
After that RonGeorg has confirmed that this is working it will be available at http://www.Marlin3DprinterTool.se/LatestVersion/Marlin3DprinterTool.msi
The build-in AutoUpdater should see that a newer version is available and try to download and install that version. If this is working there is no need to do the manual download and install.