The original universal and hitch design failed after a couple hundred miles. I created another and then I saw dbc 1218 instructable and adapted his hitch to my trailer. I moved the bike hitch frame down and adapted to attach to the existing threaded mounting holes near the rear axle. I found the appropriate size bolts at the local chain hardware in the metric bolt selection. I found after a few weeks I needed to use loctite as they loosened up.
I had to replace the wheels of the original design because of an accident and bought another $7 golf cart from the thrift store. It had a folding handle that I adapted to work as a stand and adapted a web strap from same to strap it up when in use.
I would like to have a different basket and haven't found what I would like to be permanent, therefore I am using bungees to hold it on the trailer. Just a personal quirk at this time. I am thinking of small bike tires for the trailer too if I can get them free.