On the salt feed issue, Rariitan might have re-designed it but at this point I'm not interested in their re-design.
The only issue with the original design was that they made a mistake in their choice in a valve, being the Hudson brand unit. Since the Hudson valve is a vertical activated unit (vs a lever arm and a float like a toilet valve), space constraints made it inpossible for them to just send out replacement valves, thus the re-design.
The approach I used using a vertical float switch that activates an external solenoid valve is far and away a more reliable system. Vertical float switches are available from a variety of manufacturers as are solenoid valves.
As far as Raritans culpability in this mess, yes they should have tested their system using the real pumps we typically use for water supplies on our boats. That was their mistake. If they would have tested the hudson valve in real world type systems they would never have released the product to market.