Hi Gunter, I tested UnwrapCurve over here with v2.52 on OSX myself and it's working fine for me...

One other thing to check - when you downloaded UnwrapCurve.zip, the automatic unzipper thing probably made a folder named "UnwrapCurve" with the 2 files contained inside of it.

When you copied things over to the commands folder, did you possibly copy the folder named "UnwrapCurve"? If so then that's the problem - MoI won't find the files if they are contained in some sub-folder, the 2 command files have to be present directly inside the commands folder and not nested in some additional folder structure inside of it.

I'm not sure of what else to tell you , other than to triple check the shortcut and that the files are copied as they need to be.

- Michael