Well, I had some success last night – I got the SB to connect through the Edimax repeater and to Firefly!! I had to force this by blocking the MAC address of the SB on the router. In doing this, I discovered that there is quite a long delay before the connection takes, so initially it appears that the SB has not connected. But 5 minutes or so later it spontaneously connects. I think there must be some settings on the repeater that is affecting this, although I had a bit of an email tennis match with Edimax support yesterday who insisted that WPA security is not possible via a 11b wifi connection (SB obviously does this, so not sure where the discrepancy lies – Edimax suggested that the SB actually has a 11g capable chip but is forced to use 11b connectivity in order to get a stronger signal, but it’s not something I could confirm with them). I guess the slow connection is what was making the SB preferentially connect to the router before I put the MAC filter block in place, due to a connection timeout.
Anyway, the point it that it is possible to connect to Firefly through this particular repeater, even if connection is very slow (once connected the device works well and streams from firefly with no breaks/ rebuffers – but if the signal is blocked, it could be annoying that you have to wait a few minutes before connection re-establishes). This is worth noting to those who are having problems with Belkin or other devices.