How far away is the outside antenna from the inside adapter? Pentair is going to tell you that they should be as close as possible. I had the same issue, after I moved everything so the outside and inside antennas were less than 10' apart it started working correctly.
We bought 2 of those umbrellas, it's a Crud shoot, one has a steel pole (9'), the other is aluminum (11'). Steel one definitely started to rusting after a few uses (removed each night), aluminum doesn't rust.
For the each lights to have different color or use the color swm feature you will need a transformer and a relay for each light. Transformer gets pricey at around $200+/ea and you'll also burn thru 5 relays of the 8 in the ET.