I don't know about a Mac computer but it definitely works on iPhone and iPad. It has blocked 11,000 trackers and adds for me this month. Over 1,400 just on YouTube.
Oregon sprocket grease is made in Germany by Hallbauer. It's a mineral high temp axle grease according to the SDS. I've been using it for a long time and I even have it in the gear case of an edger, a string trimmer, and articulating hedge trimmer.
Yeah you're supposed to retorque these after 50 miles. On my son's pick up It's suggested 100 foot pounds. We rotated his tires and torqued them down to exactly 100 foot pounds. He drove back and forth to school for 2 days which was approximately 50 mi. There was one lug nut a bit loose. So yes...
You absolutely can edge with a string trimmer. The learning curve is kind of steep at first and you probably will screw up the straight lines and make the edge too wide. But if you get it down it will be okay. I personally use a stick edger because I'm way quicker with it.