Please replace the existing .vmsd file with the one I attached. Ensure VMware Workstation (or at least the VM's tab) is closed when you do this in order for the file to be re-read!
With the replaces file you shoud see 8 Snapshots in the snapshot manager. Deleting the snapshots one-by-one, starting with "Snapshot 1" ... will requires the least amount of additional disk space.
I leave it up to you to backup your files before you start deleting the snapshots.
André