Sounds odd. Usually the BNF stops working with BME replacement as/if battery is not calibrated, but starts working when you modprobe -r the battery modules. I think it's intended to work that way. And with bme replaced, you should be able to recalibrate the battery with bigger capacity. I have now switched to Fxtec Pro1, but when I was using n900 I used 1600mAh batteries and they were calibrated ok.

I still think that your device does not actually faint, but shuts down instead. Where the difference is that shutting down is intended and fainting is not. Fainting happens because the voltage have dropped too low for the device to operate, which makes the device to faint immediately, without for example unmounting partitions etc. And this causes very likely some damage. On the other hand, shutting down is intended, and is caused by the os recognizing too low (but not low enough to faint) voltage and shutting down before anything bad happens. This shutting down have set to happen before the voltage drops to dangerously low, and also before battery gets calibrated. Modprobe -r should prevent those safe systems working, but somehow you still have them running. I still have no skills to help you with this, but a pity that you gave up Did you try to use the bq2700.sh script instead of bnf? Don't know why it would make a diffence though. Yoy can find it here, along with some useful info http://talk.maemo.org/showpost.php?p...&postcount=846
Those instructions to calibrate battery are not succesful, however. You probably know this already, but here's the working procedure: http://talk.maemo.org/showpost.php?p...93&postcount=2