Sentry: unit/group will wait there, until enemy is detected.
Once detected, they will do what their next wayoint orders
them to do. If next wayoint allows (depending on it's
settings - behaviour, combat mode), they will engage enemies.
Once enemies got killed, they will return to the spot of
the sentry wp (if there was no next wp).
Guard: unit/group will engage any enemies detected, in
relation to their power.
e.g: 3 10 men groups with a guard wayoint, one enemy
detected = only one group will engage.
Groups/units with a guard wp will not return to their guard
waypoint's spot, once they killed all enemies.
Sentry in combination with Guard:
Make a sentry wayoint for a single unit, where it should
observe the area, and create some backup groups with
a guard wayopint. Once the sentry unit detects an enemy,
the guard groops will go after them.
Hold: groups/units with a hold wp will engage enemies, affecting their visible area. This waypoint can be used good
to be a defend wayoint.
These are the basics about those wayoints.
~S~ CD