Does it come with a warranty?

Yes, 1 year warranty covers everything under-the-sun no questions asked refund or replacement.

Is it programmable with a timer?

Yes, but you must purchase the timer (part BS-D) separately.

I just installed the door kit, and it doesn't work, what now?

You must 24 hours after installation to know for sure if it works before contacting us.  Sometimes, the unit needs to "sense" the light and darkness.