If you want to modify the way the existing label looks you need to edit the original settings, not make a copy. If you want an additional (second) label, then you can copy the settings but you must change the label name (the first part of every setting), so that the module can distinguish between the two groups of settings. Then you can edit the second set. Note that if you don't change the positioning of the second label, it will appear either on top of or underneath the original one. If the settings are in a completely separate text file, you must also "include" the new text file, or else those settings will never be loaded. I'd suggest looking at how some other themes are constructed in order to see how this is done - then go ahead and make your changes.