You can stop using the lo n slow--your pH is low enough as it is, and the trichlor stick you have in the skimmer is also acidic, so it's going to tend to push your pH downward still. You don't want your pH to go below 7.0, or you'll risk doing damage to your liner.

Your CYA is clear because unless you've added something called stabilizer, conditioner, or balancer, you don't have any. If you plan to keep the pool open through the winter, then you'll need to add some stabilizer, because that's what keeps the sun from eating up all your chlorine. I would add a dose to get your CYA up to about the 40 ppm range--you can follow the label directions on the container, or ask here and we can help you calculate the dose. What you're looking for is often labeled different things, as I stated above, but the ingredient list should list cyanuric or isocyanuric acid--that's what you need. Until you add stabilizer to the water, the sun will quickly consume the chlorine, so don't worry about the Cl being where it is. With a CYA of 0, I would swim in chlorine levels of 5-10 with no worries--although it might fade your suits so wear old ones

Do not add any cal-hypo products or any other form of calcium to your pool water-- CH of 350 is very high, and with your high alk, you're going to get milky water if you add any more. Personally, I would use the trichlor sticks for awhile, if you don't have problems keeping your pH up, and then just switch to plain unscented bleach for your chlorine source.

Finally, ditch the test strips--they are okay for telling you if something is or is not in the water, but they are not reliable enough to tell you "how much", as you can see from comparing your test results above. Use your drop kit--but don't bother to test for CYA again until at least 4 days after you've added some stabilizer to the water--just save the reagents.

You can force your chlorine test to read higher than the 5 ppm mark--just mix a sample of pool water 1:1 with distilled water (which contains no chlorine), mix the sample well, test from that, and then multiply your result x 2. It's a ballpark, but it's still better than strips will give you.

Hope this helps!