The instructions (for basic, sludge / oil burning, and seal leaks) can be found off of links from the home page: http://www.auto-rx.com/ Click on APPLICATIONS to pick the one that fits your needs.
Since we are talking Amsoil here (the good stuff!) I'll let someone else guide you on question number 2.
AMSOIL is fine for clean phase i would extend cleaning miles to 1800 miles and rins phase to 2500 miles when working with engine thats has Amsoil in it. There additive package is really "complex" and you want to clean the metal every nook & crenny.
I would consider running the ARX cleaning phase about half way through the normal change out interval on the amsoil. You might as well get some use out of it. Spin on a new filter at that time of adding the ARX cleaning dose. I would recommend running a dino rinse however.