ahh.... now we getting somewhere... it seems a lot of gearbox issues happen after a stack with minis...
a common cause for this, especially after a stack, is that the gear lever is "forced" when the bike hits the ground, and it will put a large strain on the dogs, selectors and teeth on the gears themselves...
let me guess... the bike fell on the left hand (gear lever) side when you stacked??
If not, then yes, i am probably wrong, that's happened once or twice too, but if you've come down on the left hand side, it's probably forced the gearbox, and lunched first gear...
oh, and small shavings in the oil filter are pretty normal for a new motor that is being run in... unless of course those shavings are on the large side... then they would be your lunched first gear teeth...