Simply drag the script file directly into your 3ds Max viewport.
As 3ds Max moved toward more modern Python integrations and updated core code in versions 2024 and 2025, many older scripts broke. Version 2.28 was updated to ensure that the UI renders correctly on 4K monitors (High DPI support) and that the file paths are handled correctly within the newer Windows security architectures. Conclusion
Go to Customize > Customize User Interface > Toolbars . Find the category "Smart Merge" and drag the icon to your top toolbar for one-click access.
Ensure you are getting version 2.28 from a reputable script repository (like ScriptSpot).