Ok, here is the way i do, if its wrong, please correct me.
Downloaded Xcode from apple (last version)
http://developer.apple.com/tools/download/Downloaded the repair permissions tools (attached) ,copy it to applications.
Then download the iwi files with the attached .command (everytime there is a new version i erase the whole folder it creates under my user folder before download)
Manually execute iwi3945.xcodeproj
Go to the build folder created by the builder program under iwi3945 in my user folder, go to debug into this folder and take a look to see whether the iwi3945.kext has been created.
Go to system preferences network and check there is an network connection en0 and its not active (
check its id to see its not iwi ones and dettach the cable).
Then restart to make the system loads without any network connection.
Now after rebooting:
1.Open again the iwi3945 folder under my user>build>debug, keep open.
2.Open too system/library/extensions keep open.
3.Then open the console and select show all messages, click on clean screen and watch there is no new messages and keep it open to see new messages.
4.Drag the kext from the debug folder to the extensions folder (previously erase any other iwi3945.kext may be inside and reboot to be sure the system starts clean).
5.Quickly execute repair and set permissions, once the program finish, the kext is loaded auto and the console begins to give output messages, copy them, save into a file.
6.Clean the console, go to system preferences>network, maybe you have a new adapter, click apply, check the console, get the new log.
7.If the new adapter dont appear, add manually (with the + symbol), maybe is the last network adaptor, you have to check the hardware id, go to applications>utilities and open system profiler>network, the new iwi adaptor must be en1 and there you can see its hardware id, compare with the one you have add to network..
8 if it is not en1, then you have to hardcode it to make osx always set it as en1, go to library>preferences>system configuration>networkinterfaces.plist and change the iwi hardware adress from any enX it is to en1 (and currently en1 to the one iwi was using), restart.
9.After some clean reboots with the kext loaded, go to console,system.log and copy it,post here.
Sorry if has been a soooo long explanation, but with the normal log commands i always get blank logs, so i have to do it like this.

Hope it helps.