Hi Ali,
I've just found a few pics I took last summer of the bed guard baby mesh we made for our hightop , our van is in the garage waiting for a new stainless exhaust to arrive so can't post any other pics yet ,but, I hope these might be of help so you can maybe get camping! As the pic suggests, our little pickle is fine up there, its more often a problem getting her out in the morning from a hightop, you sort of have to look for an arm or a leg sticking out of the darkness and grab it and pull her out! Its been great being able to tuck her in safe upstairs and get a bit more comfortable nights sleep in the van.

hey presto! babyproof!
It took about a day to make, my wife and I designed it and made it so between us there was involved some very basic woodwork, machine sewing and a bit of sticking with contact adhesive. My wife makes accessories so we had quite a few of the finding ,clips etc and the leather bits but it can all be bought in a good haberdashers or dept store.
First off, we measured and cut an 18mm dowel to the correct width of the hightop, high enough to keep the pickle in and stop them escaping, then measured this off onto a strip of leather approximately 100mm wide. We then stitched 2 loops of webbing with a plastic ring on each onto the leather to attach the ceiling clips to.
We then made the main mesh from some liner-type mesh material, a bit like aertex and as used in swimming shorts and cut it to the size of the hole in the highop under the dowel.
Next, we folded the leather over the dowel and the edge of the mesh and stitched it , sealing it.
We edged the sides with a bit of webbing folded over and stitched.
On the bottom edge, we folded another leather strip approx 100mm onto the mesh and glued and stitched that too and rivetted on some large metal poppers.
Then, we added a strip of leather with the corresponding popper bottoms rivetted on and glued with contact adhesive onto the base of the bunk, out of sight.
Finally, we made 2 leather pads with leather tabs and rings sewn on and contact glued these to the ceiling of the hightop. Contact adhesive is really very strong when its gone off and you don't have to make holes in the hightop to attach the tabs this way.
Adjustable webbing and clips were then added to hold it all up.
I hope this doesn't sound too fiddly, its really not that hard to make, it just takes a bit of checking that everything is sewn ok and tight. The clips and rivets were a vital addition -in our view- because you'd want to be able to get them down in a hurry if you needed to. Also, the leather bits could as easily be thick canvas/cloth, we just had some from my wife's business and it looked pretty fancy!
It works really well as a cargo net too!
I hope this helps,
Dan