dhcp or similar could be the problem.
28% = wpa /wep , 82% is dhcp ip adress allocate and 50+% about is likely the dhcp first stage of connect or having problems talking to wifi router as a result of software chinese to english and no translator.
You can cheat using the live dvd and boot from it + cheat codes if needed.
Once inside it connect and get everything to normal working order no install / up / down grade any software only get wifi and screen to work correctly / devices recognized.
Next using http://www.gentoo.org/doc/en/handbook/h ... art1_chap6
and follow the chroot part as this would give you similar to remote access as root inside it and then emerge the dhcp or failed ones or even just run "revdep-rebuild -X" same as what you would have as text login and it should fix the problem.
Note the failed emerges and run them as "emerge -s failed somehitn name here" then try to install them and on fail see the error message and try to fix it if not fixed by revdep-reuild -X
Once you are happy about the system and confident it is okay / working type exit and reboot , likely after reboot it should all work. If not document the failed thing or save it to desktop and live dvd +chroot again + access the save bug file and post on the site here.
"emerge -uDp ndiswrapper" should list or fix anything wifi related but check .inf and if ndiswrapper is happy like it used to just in case to find the problem.
Hope this helps.