By default each Group has a different color. But you can choose a common default color
for Groups in Preferences > Colors > Group Default. See section ↑2.6.9, Preferences –
Colors Page for more information.
Once you have set a custom color for a Group as described above, the Group will retain
its color when you move it in the Group List, and the color will be stored with the Group
when you save the Group for later use. Note that you can select the same color as the
one  used  by  default:  In  that  case  the  color  (even  unchanged)  will  be  considered  as  a
custom color and will follow the Group as you move it.
4.3.5 Saving Groups
 
You can save your Groups as individual files (extension “.mxgrp”). This can be only done in the
software.
Saving Your Modifications into the Original Group File
If you have made changes to a Group loaded in your Project, you can save your modifications
as follows:
Managing Sounds, Groups, and Your Project
Managing Groups
 
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