I’ve had some issues with a number of Nanoleaf products and it’s been extremely painful getting any customer support. Numerous emails have gone unanswered. I will not be purchasing any more products, and will advise my friends and family against buying from Nanoleaf.

Yup

Ideally use the size that matches your mounting degree (60 or 90) but if what you need is sold out, the other size should work fine too. Most of us will probably mess up a few pieces of the mounting tape first time around, and even if you don’t, some pieces of tape may require replacement over time.