Go to the Parallels library directory under the user libraries and locate the Parallels directory. Rename it to Parallels.OLD. Create a new Parallels directory and copy ONLY the PVS file into it that you want to use. The .lock file is still in the .OLD directory and won't be referenced upon application restart. Be aware though, if the system is in a sleep mode, you will lose any unsaved data just like you would if you power-cycled your workstation in the middle of the day.
I personally have not had 'good' luck puting a Parallels session to Sleep and might recommend shutting the session down after each use; i do.
I hope this helps!
Bill