Error: "Error parsing XML returned from parallels. (-1)" when adding Parallels Node
This can also happen when trying to import existing containers.
This is caused by having a large number of Application templates in Parallels. The threshold appears to be around 70 applicaiton templates all installed in a single container.
Contact support for a fix.
This will be included in a future release of vWorkspace. Look for id 200644 in the release notes.