Carts seem to be working as planned. I do have a problem with a cart I took ownership of: All baskets except two will open, the two that wont open say they are already open by me.
Extracting seeds doesn't seem to change usage (or give green points) for either Forestry or Foraging. Quality appears to be based off Foraging still.
I think having tribe permissions to be able to move carts is a good idea. If it could be set up like terraforming, building, planting, etc. totem check boxes would be good, though it does not help if you have an in-active tribe leader and no permissions.
I agree with the MrDDT's basket permissions also.
Again, thanks for all your effort.