RE: CL model towing a glider?
Ifound it!
Iwas sure I'd seen a treatise about flying a glider towed by a U-Control plane and it turns out it was in a book Iown and have had since the 60's. "Building and Flying Scale Model Aircraft" by Walter Musciano (of course) has a WACO CG-4A glider set up for pick up and tow. The book is still in print and can be had from Amazon.com for about $7.00 It's a great classic and should be on the modeler's shelf.
The model has a fuselage with sheet sides, bottom and top, wings with moderate dihedral and usual rib, leading and trailing edge construction. A trapeze affair over the nose and projecting forward provide the catch point for a hook trailed behind the tow plane.
I'd copy the plans, but I'm pretty sure I'd be busting some rules, just be assured that it has been done befort and worked.