GOOD NEWS. . . . The PICTURE UPLOAD FUNCTION IS WORKING !!! The tech folks at the parent company have been able to remedy the issue. You can upload pictures once again. Thank you for your patience.
The adhesive thing is your personal preference. The book says it's not needed. If you install the bellows correctly and don't over tighten the clamp, you'll be fine. I've never used it when replacing mine and have never had a problem. You'll get differing opinions on this topic. You won't damage anything if you decide to use it but it will make for extra work next time when you have a more difficult time getting the bellows off and scraping off the old glue.
Like senior B has said its not needed but doesnt hurt, when i changed both my belows i used it for extra piece of mind, was a bit messy to use though, wear disposable gloves!