Installed handle. Overall system works very well and is quite smooth to operate. The lightweight nature of the gate is decent but the twine is not especially sturdy, though it would be enough to keep the cat in, which is the intended purpose. The fact that the bottom and cantilevered ends are wholly unsupported does make it seem somewhat fragile. Maybe something could be done to lock the gate in the closed position.
Installed new bracket assembly to raise the entire gate 4mm, which was enough for ground clearance. Also designed and printed this little knob handle that I will install tomorrow.
Weaved sisal twine into frame (took a long time) and installed it in on the client's deck. It rubs slightly against the floorboard so I designed and am reprinting the mounting brackets to raise it a few millimeters. In the limit I want to make a handle, some locking feature on the wall end, some soft end cap on the exposed extrusion edge, possibly convert away from 3D-printed ASA to metal components, and make the actual gate a bit more sturdy by running some reinforcement stringers (maybe steel cable). 
Cut 2020 aluminum extrusion for the gate. Drilled holes every inch along each bar for eventual threading of wire. Assembled the entire frame along with the carriage assemblies. 
Printed another set of the components to hold the gate at 2 points.
Designed 3-unique-piece wheeled sliding carriage for the gate. Printed and assembled some of the parts and tested on a short length of 2020 extrusion. 
