One of the common problems we see reported is that after downloading the simulator it will then uninstall itself and restart the download. This becomes an endless installation loop where after finishing the download deletes itself and then tries to reinstall.
This is caused by only one of two different problems:
1) running the launcher.exe from inside the zip file that you downloaded from our website will cause an installation loop. The files inside the zip file should be unpacked to a folder and then you should run the launcher from that new folder. The problem with running the launcher from inside the zip file is that all the files downloaded will also be placed inside the zip file and this causes the installation loop.
Video on correct install process -> https://youtu.be/KJmw98Px5F4
2) some antivirus products (usually AVG) like to interfere with downloaded files and corrupt the data as it is been downloaded. The fix to this is to put an exception in your antivirus product to tell it to ignore the folder where you have unpacked the launcher.exe. This will stop it corrupting the downloaded files and end the installation loop.