Markus
If you have the [NR] bit set low, then the PRES input can be used. If PRES is low, then the CHG and DSG FETs can turn on. It is is high, then they will open. This may provide the switch functionality that you need.
The cells have to be connected to the gauge all of the time or it will go into shutdown and you have to apply voltage to the P+ input to wake it up after the cells have been reattached. In the case of the notebook system, the cells are always attached and the device goes into Sleep mode when the pack is removed. There is very little current draw in this mode as well. The requirements for entering Sleep mode are in the TRM, but basically you do not have current draw and the SMBus pins are pulled low. The pack will exit Sleep mode if the SMBus signals get pulled up or if current is detected through the sense resistor. In the case of the notebook computer, if the device goes into Shutdown mode, then the pack has to be attached to the charger to wake the device up.
Regards
Tom