Thanks Hielkenator for all your advices.
Actually I have finally fix my problem, by updating manually the boot.dol of my cfg loader in apps directory of the wii sd card, by this one
http://v01.mikeserver.de/cfg/cfg70r78.dol
For people read this, to solve the same problem, don't forget to rename cfg70r78.dol to boot.dol of course
I am soooo happy it finally works, so now if i want play wii games with cfg loader i just have to turn off the wii and plug my ntfs WBFS external usb hard disk (use wbfs manager windows to copy games on hdd).
And if I want play gc games, with the same cfg loader, i turn off the wii and plug my fat32 usb external hard disk ( usb:\\games\ (any name of game) \game.iso ) (use cleanrip homebrew on wii to dump my gc games)
And everything with covers, so cool!! ^^
Seems my problem was to be unable to update anything directly from the softwares installed on my wii/sd card (cfg loader, loader gx, nintendont, etc)...
Maybe because in my country google website (as well as youtube facebook etc) are forbidden... and seems now many update downloads come from docs.google.com
I don't know.... anyway, if you are stubborn, and don't stop to read and search online, and update files manually, you finally get rewarded :-)
And thanks again to all the scene!!!!!!!!! It's an awesome parallel world that we have here :-)
Sometimes I feel i spend more times to make everything work correctly, or do some collection, than really play, but it's an other debate hahaha
And what about fast ssd external usb hard disk for wii (as well as ps3 and xbox360) is it working and really faster the games loading times ?
Also those gc games with nintendont are as beautiful as they could be with dolphin emulator ?
Anyway with nintendont and cfg loader it's very convenient.