https://www.securitywarehouse.co.uk/catalog/intruder-alarm-c-36/door-contacts-switches-c-36_44/knight-g2-surface-contact-with-tact-tamper-and-selectable-res-p-3868.html
Is a surface contact that is compatible
No the cp8l does not support tag
I would suggest an upgrade after 10 years
Pir wise i like the Honeywell or hkc
Wireless requires a hybrid panel
Again look at the hkc best wireless Imo or the honeywell
Both panels support apps too