First you need to tell the controller you have a wireless receiver.
That is done in the "Expansion Modules" setting.
Do you have the docs for the Wireless receiver?
Then you need to wire in the contacts, motion detectors or learn in the wireless contacts to the receiver.
Then you need to tell the controller what the contacts are for.
The controller doesn't see any electrical difference between a door/window magnetic reed switch and a motion detector. They are just circuits.
You tell the controller what to do with the contacts by setting the zone type in PCAccess.
So a motion detector is usually Away Interior (meaning it is only monitored for alarm in Away or Vacation mode) or Night Interior (meaning it is monitored for security in Night, Night Delay, Away and Vacation modes).
You can make a motion sensor Perimeter or Entry/Exit if you want, but they will be active during Day mode, so you would set them off walking around an armed house.
You could also use them as "Auxiliary" type if you were using them purely for automation purposes.
If the wireless contacts are on doors, they are usually set to "Entry/Exit". This will allow an Entry/Exit delay before triggering the alarm.
If it is a seldom used door, like the side door of a garage, then I usually use "Perimeter", which offers no delay so the alarm sounds instantly.
Windows are usually set to "Perimeter".
Read both the Omni Install and User manuals.
The documentation for PCAccess is sorely...lacking.
After reading the manuals you can click through the various setup menus and find most of the settings fairly readily.
Do you have a controller already installed and are adding contacts, or are you starting from scratch?
Do you have the Installer version of PCAccess?