It turns out that the + on the micro USB header was loose. I was able to just heat up the pin with my soldering iron, and get it stuck on again.
I also did pin the USB cable in there with a zip tie, to attach this I drilled two holes in the dibond. I routed the cable from the melzi side, and around behind the dibond through the other loop of the zip-tie so now even if you yank on the USB cable it won't (hopefully) pull on the melzi at all.
I'm still interested in the bluetooth module though, but at least this will make it less of a critical issue for me.
I also did pin the USB cable in there with a zip tie, to attach this I drilled two holes in the dibond. I routed the cable from the melzi side, and around behind the dibond through the other loop of the zip-tie so now even if you yank on the USB cable it won't (hopefully) pull on the melzi at all.
I'm still interested in the bluetooth module though, but at least this will make it less of a critical issue for me.