i would like to permit to my users to edit their username so i dont need to help them each time
there is a solution ?
thx

You could add the field to the usercp and to the usercp file, but are you sure you want every single user to be able to edit their username all the time?

i have a multiplayer board with to much people and some of them need to change because of having same nick in game and board too

it's one solution

1 more solution is to permit them to change only when needed but in this case i need 1 more admin allowed to change and i don't like it too much

i don't see big problems to let them change so i think i can get this solution
i'm right ?

you could do it this way: promote a moderator on your board to a "small" admin with only access to the "user" parts of the admincp, did this on my board to give my staff the possibilty to add new members inside a private board.

i will ... i'm thinking is not good to have too much hacks and i will try a solutions without code modification

Good idea.

Remember, people being able to change their names can also result into some other modifications not working.