Hi @spiemel, I was indeed able to reproduce your problem on my own laptop (although interestingly it does not seem to occur when an external display is connected via docking station vs regular DVI cable).
At any rate, I discovered that If I uninstall the Tobii software, disable the laptop screen, the reinstall the software using the external monitor as eye tracking monitor, then reenable the laptop screen.. the power stays on.
I should mention that I disable my laptop screen via the standard Windows display settings (and set the external monitor as main display).
Can you kindly try this out and let me know how you get on?