I installed a copy of bt4 to my hard drive and earlier had it persistent on my usb drive.
I run this on an Acer Aspire One d250 and got everything working .
I had the same problem as in the post above and in order to fix it i had to do the following:
For some reason BT4 pre starts up with my wlan0 wifi card in monitor mode. I actually like it like this since I can quickly open Kismet and such without any command mambo.
to get wicd network manager working I would have to bring my wlan0 down from monitor mode. there are many ways to do it but the easiest for me is:
#airmon-ng stop wlan0
then i bring up the networking and wicd with:
if you already have kde running you can now go to KMenu->Internet->Wicd Network Manager
if you doc this before you startx then it will sit in ur taskbar.
They key to this was taking the wlan0 or ath0 out of monitor mode which it starts in by default.
Hope it helps...
Love BT4 Pre...