Make sure the water has been circulating for 30 minutes then test for pH, TA, CH. You should have zero FC/CC and zero CYA with new water. Get your pH to 7.4 if it's high. Unless your TA is less than 100, then you can leave the pH at up to 7.8. Only lower if it goes above 7.8 in that case. Then get some FC in the water immediately, roughly 2-4 ppm. Then add your CYA. I would suggest using pure CYA to get it up there rather than tablets, unless you have a glut of tablets to use. Save the tablets for when you're going to be gone for several days. If you do choose to use tablets, ONLY use them in a floater, not in the skimmer. Keep track of how many you use to know how much CYA you have added.
Your SWG may not function very well if water is below 70 degrees and you may have to run at higher output. Keep in mind that your salt level displayed on the controller is also affected by temperature. At low temps, the reading will likely be lower than actual.