After making all bones posable, then adjusting any shape key, the expressions and face units break

[Jake]

Title. Basically, after making all of the bones posable, I get this error message:

Python: Traceback (most recent call last):
  File "C:\Users\ME\AppData\Roaming\Blender Foundation\Blender\3.0\scripts\addons\Diffeomorphic-import_daz-22129e439cba\error.py", line 208, in execute
    self.run(context)
  File "C:\Users\ME\AppData\Roaming\Blender Foundation\Blender\3.0\scripts\addons\Diffeomorphic-import_daz-22129e439cba\figure.py", line 468, in run
    self.addExtraBones(rig)
  File "C:\Users\ME\AppData\Roaming\Blender Foundation\Blender\3.0\scripts\addons\Diffeomorphic-import_daz-22129e439cba\figure.py", line 734, in addExtraBones
    self.updateScriptedDrivers(rig.data)
  File "C:\Users\ME\AppData\Roaming\Blender Foundation\Blender\3.0\scripts\addons\Diffeomorphic-import_daz-22129e439cba\figure.py", line 583, in updateScriptedDrivers
    vtargets,btargets = self.getVarBoneTargets(fcu)
  File "C:\Users\ME\AppData\Roaming\Blender Foundation\Blender\3.0\scripts\addons\Diffeomorphic-import_daz-22129e439cba\driver.py", line 155, in getVarBoneTargets
    for var in fcu.driver.variables:
AttributeError: 'NoneType' object has no attribute 'variables'

location: <unknown location>:-1

After that, I can move both the face bones and create expressions with the Daz units. However, when I adjust any of the shape keys in the shape keys tab, basically all of the movement provided by the Daz expressions disappear and neither does adjusting the bones do anything. What is going on? I’m using the 1.6.1 preview version.