Detecting Uniducial marker only on specific Rotation.

Hello,

I am using the Uniducial library to track different objects on a multitouch tabletop using Unity. I have a game scene, which has different triggers setup. When a marker is correctly placed on a trigger (with specific ID) then the trigger is turned on and it shows a message that if it is the correct object. This is currently working well. Now, I want to add rotation to the markers. So, how can I detect a marker on a trigger only when it is placed at certain angle ? (I know Uniducial allows rotation, but I tried it and it doesnt work well.) Is there a better way to do it?

Thanks