I know the basics of upgrading, but what I don't get is how all these people are running around with (assumedly) highly upgraded weapons. So you put the rune in one of those 8 slots, and you click begin... isn't that like 7/8 chance of failing?

I failed going from +2 to +3 five times... having to rebuy my weapon five times, and wasting about 8 runes.

Could someone please tell me how to upgrade properly?

chance of failing is 6/8. doesnt have to stop at the box that u put the stone into. if its on the same line it will work. say u put the stone into the top center, if the thing stops at the bottom center, it will work because its on a line.

most people got their high weapons from doing kingdom quest. thats how i got my +6 staff.
n no, there is no way to upgrade properly, the thing is pretty much random.

It's a game of luck but so far i made a +7.. theres a technique to get +1 - +3 w/o failing then the rest i just guessed