I managed to get the Edimax Wi-Fi dongle working eventually, using the Wheezy Debian OS plus the script by Mr. Engman and a wired Ethernet connection. This worked faultlessly for many days until I foolishly did a rpi-update. This then updated the firmware and reported no errors, so I removed the wired ethernet, plugged in the dongle and rebooted. No connection with the old 'wlan0' not found etc. None of the suggestions found on the forum seem to help. Without sounding too ungrateful to persons who slave away getting stuff to work, I do find it odd that the 'official' Debian OS for the Rpi is still without a reliable wifi setup. Of possible other interest to other beavers who try to sort out problems, while my wifi worked perfectly as described above, I was never able to get mp3 files to play even using the modprobe command that did work before I managed to get the wifi to work..... frustration. I do look forward to an OS that has the basics all working soon. I do recognise this is all voluntary work... thanks to you all.