Assuming that is the default picker template that ships with mGear, and they didn’t edit it, then yes. That is the problem. Sort of. Actually ignore “controllers_grp”. I’ll explain.
The “Select ALL” button in the default picker template that comes with mGear looks for:
(It doesn’t have to be in a namespace. But if you don’t have a namespace, then it would only work with one character.)
The confusing part here is that in mGear “_grp” is actually referring to a selection set. The word “group” is a throwback to names in Softimage XSI. Groups were collections of objects, just like selection sets in Maya.
So the picker is looking for a selection set named rig_controllers_grp
Your rigging artist used a transform group named “controllers_grp”, which I guess is the parent that holds the rig? Anyway, ignore this. It doesn’t matter! It’s just a misleading coincidence that the name ends in “_grp”
They also seemed to have deleted any selection sets. In a default Shifter build, assuming your rig is named “billy”, you should end up with selection sets like this:
So if you want that button to work, you’re going to have to make a selection set that has ALL of your controls. Or ask the rigging artist to fix that.
IF you had a character named “billy”, and you DID have a selection set named “billy_controllers_grp”, then yes, you would also need to either:
- Rename the selection set to “rig_controllers_grp”
- Make a duplicate selection set and name it “rig_controllers_grp”
- Edit the code in the picker. And change that to “billy_controllers_grp”
- Write some different code that is able to find all your controls without a selection set. (For example, by *_ctl name.)
Bonus information: When you say “use the picker”, I want to point out an important thing. The template picker that ships with mGear is not “the picker”. It is just a template that ships with mGear as an example. It should work by default with a standard mGear Shifter Biped template.
But if you make any customizations to the rig, then you almost certainly also have to customize the picker. The Anim Picker is a tool that is helpful for making custom selection buttons and script buttons. It is not meant to work out of the box with any rig that is built by mGear Shifter. That would be impossible.
If you want to test the Anim Picker and learn what all the buttons are doing, then you should build a quick Biped template from the Shifter menu. Then it will be compatible.
I hope that was all clear! Sorry I didn’t have time to write a shorter reply.