I've installed this on 3 comps , Win 7 and Win 8 with no errors, including one that had it previously. Everything worked flawlessly, no errors.
If you are installing on a system that had it previously, make sure you run task manager and verify that it isn't already running.
Check your neos-data folder and remove neos.lock if it's there, and launch the wallet again.
If Neos isn't properly shut down (e.g.: a system reboot or killed through task manager) it won't remove the garbage lock file which indicates to Neos.exe whether or not it's already running. This would explain why there is a unique case so far, as this can only occur during an improper termination or reboot. I'll work on coding a hack for this as I had coded this lockfile in to prevent people from running multiple controller processes which could lead to issues. I'll post an update.
Best regards,
syntaks