Yes, you can edit your posts. In the top right hand corner of the post there should be a small edit button.
On the TA test, keep adding drops as long as the color continues changing. If you add a drop that doesn't change the color any further, you are done and you do not count the drop that didn't produce any further color change.
Yes, hot water will speed up dissolving CYA, but it is really just a waste of time. It still won't fully show up on the test right away. Just put the CYA in a sock and put the sock in the skimmer and relax and let it dissolve. There is no reason to make extra work for yourself.