Things have changed a little bit and my system setup is now:
Motion Sensors --> MR26A X10 RF receiver --> Misterhouse --> LMCE DCE
MH sends a tripped event with value 1 to LMCE when motion is detected and sets an internal timer. More motion refreshes the timer. When the timer expires a tripped event with value 0 is sent to LMCE. I could find no way to program this logic in LMCE, and also there is no support for the MR26A, so MH is the best option right now.
I then setup LMCE to turn lights on and off based on the security sensors.
I have some X10 wall switches which I have defined as lights. I then setup respond to events to do things when the light is turned on or off.
What I am missing:
There is no way to say in the advanced criteria page "Do this, if this sensor is tripped, and nobody is watching media in the room, or if this device is on" as there is no way to add more than one event for the criteria. I wanted to have an override switch I could use to enable and disable motion operated lights - hence the last part of my desired criteria.
I also can't find a way to say "if it is 2 hours before sunset" in the criteria. Is this possible?
I wondered what Room Mode was in the criteria - perhaps this would let me do the "if nobody is watching media in the room"?
Also how can I do "if the house is not in sleep mode"?