I am looking for some advice.

My mother's house was wired up for an alarm system at one time using
security screens, door switches and some window switches.

For some reason, the wires going to the control box were pulled up
into the attic.

Can I check each wire using a continuity checker and opening/closing
each door and window?

One weak area has has two "doggie" doors that are big enough for
someone to crawl through.
(One goes from the yard to a outside room and the other from that room
to a middle room)

I can't see any way other than getting rid of the "doggie" doors.

Thanks,

Andy