Changes in lighting trigger MxAnalytics

Hi,
Since old-fashion motion detection has some clear disadvantages over MxAnalytics, I tend to use that last to detect motion and presence in a room, and on a driveway. The room is typically a ceiling mounted C26b, night with IR source. The driveway is done with the T26b cam with day lens.

However, I notice that on both camera’s MxAnalytics motion often gets triggered when lighting conditions change. With the default motion, this can be avoided by adding reference windows. But how do I adapt MxAnalytics? On the T26, source of light are headlights coming from cars passing, or leaving the opposite parking lot. Their headlights light up the driveway, triggering motion. On the C26 it is mainly sunlight that enters the room after a cloud disappears, or lights turning on/off

Also, how can I determine presence? For example, somebody sits on a table. I used to add sensitive motion fields on the table, so the slightest movement of a hand or arm triggered motion, sending out an IP message. But with MxAnalytics, motion must be more pronounced to trigger, even on lower settings. Is there any way to have detection? I was thinking on duration of stay, but this is also limited in time to 300sec. Any tips and tricks?