I basically came to the conclusion that your CH levels were due to "calcium scaling" because your pool was new and there was not enough calcium in the pool, raising your levels. There is no other explanation besides testing error, but you are using the TF-100, so this is not the issue at this point. Over time, your CH will drop, especially with probably a bad winter here in NJ of snow and rain.
Do not plug in now and target numbers in, just current readings as I did in Pool Math to come up with the CSI. I would not put too much effort of what the figures mean, probably way beyond our knowledge as only a few forum members could answer this one. If your CSI is within ranges, then you are fine. Plug in the current testing figures and your CSI ranges will change. As I wrote previously " If you go back to Pool Math, and use the same figure for current (NOW) and Target, and adjust levels to 12 (50% of shock level based on CYA), PH to 7.5, TA to 80, CH to 500, CYA to 60, and Salt at 3400 with Temp. at 64*, your CSI range is -0.27 and -0.27. (Well within recommended ranges)", this is what you will have. That simple.
Your CSI changes to a higher level, almost over the normal levels based on water temperature dropping into the 30*'s, but I remember a post from other forum members stating that as the temperature drops, your PH rises. So if your PH would rise to 7.8, even at low water temperatures, you still are fine.