My post here is to help people like me who at first glance read the wiki and thought "Woaaa that looks easy!"
And when you really try on the board after spending bucks on it, you are having hick ups because of the obsolescence of the wiki.

1) if you are trying to install mjpg-gstreamer or motion or whatever... you have to change the link in opkg.conf. The link you have when you build your system is a link on 8devices website. But loads of things are missing in this repository and "opkg install motion" will fail.
Instead change to this:
"src/gz snapshots http://downloads.openwrt.org/snapshots/ ... s/packages"

2) if you are trying to directly install a package with the link they provide like this:
"opkg install http://downloads.x-wrt.org/xwrt/kamikaz ... ramips.ipk"
This is NOT working either. the link to this website is dead. and the funny thing is that the website itself says that they don't support Kamikaze yet...
"Support of OpenWrt's upcoming Kamikaze firmware is coming soon"
Again use this link: http://downloads.openwrt.org/snapshots/ ... /packages/

I've only try to stream a webcam throught Wifi for now so I might find other "hick ups" as I'm going further the wiki, I'll try to update this post.

Hope this will help someone.

Thank you for your notice! We will update wiki soon.