My first bit of advice is to cool your jets!
Theres nothing wrong with the g/box action. At first they are tight but they start to loosen up at about 20,000 Klm's and at 50,000 Klm's they are getting near perfect.
If you speed up the clutch hand lever pulling in action slightly and slow down the foot changing action slightly, you may find that this will allow noisless changes.
Also standing at the lights in neutral pull in the clutch, hold off for about 1/2 a second and then push (not slam) the foot lever through to first. You will then get 19 times out of 20 a noiseless insertion to first gear. If this doesn't work, then roll the bike ever so slightly and it'll slip in like a hot knife through butter!
There are many more little things and it does take practice I grant you, but the box is only as good as the operator.
Start by using lower rev changes from 1st to 2nd and take it from there. I'd suggest changing up at around 2,500 - 3,000 RPM until you get the hang of it.
Mick.