Confused about PVM file(s)

I was trying to setup a "clone" of another Macintosh. There were several abortive attempts.

I finally got a working Virtual Mac. The Finder reports: 1 Hard Drive with the size of 548.9 GB (113 GB available)

But I have 2 PVM files.

Renaming either of the PVM files results in a broken Virtual Machine.

Is this normal?

I'm new to Parallels, so I'm not sure what info to give.

Host Machine

• iMac
• OS = 10.8.2

The VM

• Name = Old iMac
• Hard Disk 1 = Old-iMac-0.hdd Plain disk, 512 GB
• OS = 10.7.5

The PVM files:

• Old-iMac.pvm Size = 549.76 GB Date last modified = Yesterday (when the VM was created)
• Old iMac.pvm Size = 42.3 MB Date last modified = Today (corresponds to when I run the Virtual computer)

What happens when I rename the files:

• Renaming Old-iMac.pvm to Old-iMac.pvm1 = Virtual Machine gives an error "Unable to connect Hard Disk 1" followed by "There is no operating system installed in this virtual machine"
• Renaming Old iMac.pvm to Old iMac.pvm1 = Power button in the VM list changes to a "?" symbol - Launching the VM gives an error "The virtual machine is not available". If I choose "Locate" and pick the other PVM file (Old-iMac.pvm) I get the following error: "The specified location contains another virtual machine."

So to me it kind of seems that 1 PVM has the meta data for the VM and the other PVM has the Hard Disk for the VM. Is that normal? And if not, how do I correct it?