Thanks for your interest in UCS!
The current version of UCS you can find online is not compatible with gripper.
But we're about to release a new version of UCS within two days.
And the latest UCS V1.1.7 is compatible with gripper!
I tried UCS V1.1.7 with gripper. It works, but you'd better set certain delay time for the gripper to stretch and close.
As what I've tried, 5 seconds are enough for a complete "close" of the gripper.