While upgrading from Komplete 13 Ultimate to the 14 version today, I started using Native Access 3.0.1 for product downloads. I noticed that some installations didn't complete within a half hour or more after the download had finished. Successful installations finished in less than a minute after downloading.
The pattern seemed to be that, if I queued three or more installations, the first would complete, the second and third would both download, but the second would get stuck on installing. I can't be absolutely certain of that pattern, but it happened that way twice.
If I exited Native Access, then started it again and chose the same product to install, it would re-download and the installation would work fine. (Why it downloaded again with the .iso already sitting on disk, I have no idea.)
Switching back to version 1.14.1.156 let me schedule -- and complete -- multiple installs with no problem.