R/R issue?Please Help!

I've got a 1990 VFR750F and she's been ridden every day for the last year (My main ride) with no major issues, until yesterday morning. I did extensive research on the Interceptor before I bought her and knew going into it that there was a history of R/R issues, however my experience has been a little different from the ones I've been reading about. Mind you, my bike has a relatively new aftermarket regulator, installed shortly before I purchased it. Basically: I choked the bike as usual for a cold start, put in the key and turned it until my dash lit up, then switched to start; nothing out of the ordinary. Then I hit the ignition and the engine turned for a split second then everything died, immediately. No lights, no engine turning, nothing. I immediately checked all of the fuses and they're all intact, however the plug from the wiring harness that connects to the main fuse hub (Bikebandit.com has this part listed as “SW, STARTER MAGNETIC” but doesn’t go into specific plugs on the harness) has a hole melted through it, right down to the prongs. Again, no fuses blown. Any idea’s as to what could have caused this? It’s been 1 day and I’m having riding withdrawals!! I’ve included some pictures below. Thanks so much!

 

Oh man. another dicey one, well first off check the battery for voltage. to make sure it's not a bad battery. I had the same thing happen to my lawn tractor, turned out to be the battery where it blew a cell at that same moment a load was initiated. After that, repair whats is obvious, like that hole in the plug or at the least find out what the connections looks like, doh! something got hot. what I find in a many is the plug connections get corroded over time, dirt water etc and they finally don't make a good connection therefore cause a weak link and a weak electrical connection will cause heat. after that then you work your way through all the fusses as you mentioned but makes sure where they slide in good too. follow the electricity with a volt meter as you move along. check all grounds too. This process could drive you crazy just make sure you have your favorite beverage on hand and the dog is out of the way,. Sorry not much help it's one of those be there situations. good luck, lets us know how it goes.