For those who may be interested...the email sent by forum member CarlJ...as referenced above...detailed a situation identical to mine. Carl was able to "pop" the appropriate "gear axle" back into its "hole" in the underside of the crane and gain control of the rotation of the crane body and boom.
I was able to see the same situation under my crane and "skillfully" popped that gear axle back into the proper hole. Now the crane rotates as advertised.
For the record, Charles Ro was ready to accept my return in exchange for another working crane...which they said they would test for me before sending it out. Of course, I would have been "out" the shipping charges.
I still have issues with the crane moving back and forth on the special gantry track...using Ross...I get a lot of wheel spin...and very little movement. Something is out of whack...hopefully, I can remedy this problem myself.
Thanks to all who posted and emailed!