My first post on a new forum to me. So be gentle!

I have a 07 1.9tdi Jetta with some very confusing electrical issues. Firstly, i was travelling home from a night out and the 80amp alternator fuse blew and i got the battery light on after a short time. The engine seemed to heg abit before it blew. Had the alternator checked and it tests ok. Checked all wiring and earths and they all test and appear ok. Replaced the fuse and the main feed to the fuse board gets extrememly hot. Almost to the point of melting. Tried running a new supply wire from the charge alternator and still got the same thing. Any ideas what i can check next?

Second problem is a spooky one, the boot opens on its own whenever it feels like it. Car has to be open for it to do it but it doesn't when its locked up. Theres no time limit for it , it just pops open! Have checked the wiring from the lock into the boot itself and theres no damage or other issues. I suspect it's getting a pulse from somewhere but have no idea where to start looking.

Thanks for taking ages out of your lives to read this and i hope someone has some ideas as to where i go next with either issue!
Cheers