Nope, while running multiple VMware Workstation / Player instances work fine it wasn't really designed to keep the .vmls file from ending up getting corrupt.
This is probably one of those areas where we have to count our blessings (the running multiple instances working OK part) and take the inconveniences on top. It is an issue that can only be resolved by VMware. Nothing you can do to prevent it apart from not editing the VM list when there's multiple instances open.
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Wil
| Author of Vimalin. The virtual machine Backup app for VMware Fusion, VMware Workstation and Player |
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