Thank you for the report! Glad to hear that you love the tool ^^
I believe the problem is the preferences.dat file not being correctly converted to the new .ini format. For now if you delete the file NAW should open correctly. Let me know if that is the case. It should be located at:
C:\Users\Windows 10\AppData\Local\NostalgicAssetsWorkshop\preferences.dat
I'm taking a look if I can fix the conversion and will update the status here.
edit: Hotfix uploaded. Please let me know if that fixes it. Thank you very much!