I finally have my rt2870 "Wireless n" USB stick from Edimax EW-7718Un working.
Given the lack of support i received from anyone, i am sharing my experience for those who stumble across these instructions. They should work for any rt2870 based USB stick.
If you are like me and know little about Linux and therefore, no doubt choose to edit/create files on windows rather than try and use vi, two things to remember; -
a) you need to use an editor that allows saving with LFs instead of CRLFs (I use EditPad Pro - which also allows for conversions, etc)
b) when you ftp files up, you need to remember to set their attributes (i use filezilla)
I have seen a number of drivers posted and the one below works (with no WPA support), the other driver posted with WPA support i could not get to work).
http://www.dream-multimedia-tv…fa419a29450f925b0b751ca2c
I have also read that these drivers may conflict with the rt73 drivers if installed - i did not find this a problem and still have my original stuff installed as-is.
Step 1
download the drivers from the link above, posted earlier in this post.
extract to your local drive and ftp the \lib directory to your dreambox - remember to set the attributes to 644 afterwards
\lib\firmware\rt2870.bin
\lib\modules\2.6.12-5.1-brcmstb-dm800\kernel\drivers\net\rt2870sta.ko
Step 2
modify the rt2870sta.dat file enclosed with the key information below;
CountryRegion=1 ; value should suite most of europe
CountryRegionABand=1 ; value should suite most of europe
SSID=MYWAN
NetworkType=Infra
WirelessMode=6 ; this value is 'n' only - see the iwpriv_usage.txt file for the options available
AuthMode=WPA2PSK ; you need to set whether open or encrypted
EncrypType=AES
WPAPSK=MyPassWord
-------- ; next add the following lines to the end of the file
ONBOOT='yes'
BOOTPROTO='dhcp'
STARTMODE='auto'
copy the saved file to (case sensitive);
\etc\Wireless\RT2870STA\rt2870sta.dat and set attribute to 644
Step 3
add the following entry to \etc\modules.conf;
alias ra0 rt2870sta
Step 4
create the file \etc\rcS.d\S38wireless (case sensitive) ** Attributes need to be 755 for this to allow the recognisition at boot time.
add the following lines;
modprobe rt2870sta
ifconfig ra0 inet dhcp up
Step 5
edit the file \etc\network\interfaces and add the following entry to the end;
# WLAN
auto ra0
iface ra0 inet dhcp
Step 6
to set the WiFi card as the default, create the file \etc\default_gw and the entry;
ra0
now in your telnet session, type "reboot"
Testing
login as root and type;
ifconfig
you should see the "Wireless n" interface and card type etc listed.
type;
iwconfig
you should see the wireless lan settings on the card i.e. SSID name, encryption key, etc ** see my notes below.
if you don't know what the dhcp address should be, you need to type the following as a work around;
ifdown ra0
ifup ra0
iwconfig
you should now see the "Wireless n" interface with an ip address.
*** Notes
- iwconfig; doesn't seem to show the ip address (when using dhcp) after a reboot. however, the ip address is correctly set and does work (toggle down and up to refresh if you need to know)
- iwpriv ra0 show; doesn't actually show the settings of the card
- if you use a static ip address instead of dhcp, i believe the GATEWAY=xxx.xxx.xxx.xxx needs to be in the rt2870sta.dat file above (but haven't tested)
- this was done on a dm800 using info from a variety of sources, but should work on a 7025 as well.
Best of luck.... still can't stream HD smoothly over Wireless n though 
