Well Igor, if Parallels would produce a product which admins could RELY upon not to break when you do updates, etc., then my asking for confirmation that someone has successfully used it already, wouldn't be necessary. Your solution is typical, do a backup. Yes, I have a current backup, every morning. So the solution is do the update, and if it's faulty and breaks something, restore from backup. Wonderful, that's what we should count on, spending our time restoring from backup when faulty programming on Parallels side results in breakages of our software and inconvenience to our customers and ourselves ... but hey, I've got a backup.
Your comment was completely uncalled for, and probably I won't bother coming back to the support forum to look for help and answers when Parallels staff treat their customers rudely.