Don,
It is a mystery to me why you are not picking up anything from your tower and/or the ADSB is not showing you.
When you fly over/near it, does it appear to be working (transmitting) on your iFly tablet?
With mine, I can see the little blue tower "transmitting" as shown in this photo.
Concur this is a sketchy system and it is on-again, off-again around here. Some days it works fine, some...not so much.
With all "new" systems we see "teething problems"...and because this was not an optimal roll-out or design implementation plan, I expected some of this to happen...
Sorry it is not working as well for you. I suspect with maybe more towers it might get better.
What are OTHER pilots at your airport saying?
Mike N714AJ