I've successfully installed yamas on a clean device last week.
What has been done:
1) update device to the latest available firmware (OTA works)
2) you need to enable extras-devel repositories to install all required dependencies, here is the how-to-do this https://wiki.maemo.org/Extras
3) install power-kernel (probably the latest one). I've done this from Faster Application Manager.
4) install patched wifi driver. This can be done from Faster Application Manager - install .
E.g. you can install Wlan Driver Selector Applet
http://talk.maemo.org/showthread.php?t=73682

5) if you install power-kernel - you need to reboot device and apply custom kernel settings


After that try to install yamas from the repositories or from Faster Application manager, both methods shall install all required dependencies automatically.