1. The phone must be switched off when connecting it
2. You need Gordon's Gate Flash Driver installed on the computer (I recommend using Win XP)
I have successfully unlocked half a dozen w890is and a k660i using Aerix. Two problems I've experienced:
1. Aerix could not communicate with the server. It must have been down that whole day. When I tried it the next day it was working again.
2. When unlocking a w890i which was debranded after "Server communication..." follows "Phone restarts...", this is where the process froze. To fix it I disconnected the phone (leaving Aerix running), replaced the battery and connected it again while holding down 2 & 5, luckily the continued and the phone unlocked successfully.