The window does work really well, I wouldnt change it now, We also made it large enough so we can get inside the ark through it, which enables us to reach in and assist to the piglets if needed. Also use it to bed them down, this way the mother doesnt see you and you can make sure you arent putting to much starw in for the piglets to burrow under.
The chicken wire sounds like a good way to help prevent them sneaking out, maybe a good idea to dig it in the ground a little to prevent them digging out, they are also very good at this too, they are little escape artists but they never seem to venture far from their mum though.
