Are you saying that when you put one of the un-programmed switches into discovery mode, upstart can not find it?
What brand of switches and what phase coupler are you using?
It hard to believe you have a powerline condition that would prevent the discovery of 35 switches. You can always use the install/replace feature in upstart and swap out one of your working kitchen switches to see how the non discoverable switch reacts.
I have only had one problem with a non discoverable switch do to a 3KV ups on the same circuit as the switch was on, this was solved using a split phase repeater from PCS.
We have not really dealt with HAI switches, but it's the same technology as PCS and Simply Automated and they have been solid, in just about every install we have seen. If the install/replace test does not work I would be questioning if there is a lot problem with this production run.
Bill
www.homeautomationnet.com