agv mobile robot and UR5 attachment error

So I am working on making a UR5 and mobile robot attach and work under a custom Force or Step Route. when I don’t use Custom route this works fine. the robot arm takes the part stores it temporarily on top of the mobile robot and places it normally on the other work process. but when I create a custom route. I get this error:
"Traceback (most recent call last):
File “Works AGV Resource::Brains” , line 694, in OnRun
File “Works AGV Resource::Brains” , line 1081, in Pick
TypeError: doEoatChange() argument after * must be a sequence , not a NoneType

can someone help me out, i did exactly what "simulate Mobile Robot - 3 video on youtube did and he did not get the error and it worked fine.