https://cgi.ikmultimedia.com/ikforum/viewtopic.php?f=12&t=11405
After that I found the very simple solution to the long filename problem that happens if one unzips the installation folder to deep in a subfolder. I just moved the installation folder for part 1 to the root of that drive and then the installer worked without issues

Just want to share this experience with you since it can be useful information to anyone trying to install this instrument. I also made a ticket to the support about this information since it could be useful to share in the FAQ