I don't think you can get TOO much info on the 820/830. Check out the webinars, Yahoo groups, websites from generous users, Amanda Whitlatch, etc. Surf the net. There is a lot of capability and functionality in these sewing computers and a lot to learn.
I am also keeping a separate diary with info and tips and self discoveries, tension setting that may be specific to my machine, etc. It is just too much info to keep in my head. At my age, the "disk is full."
PS. My 830 arrived with the language set to French, the manual in English, and the DVD in German.
I set the machine to English, downloaded the "Final 830 Manual" from the USA Bernina Website, but there is no hope for the DVD. Of course, the one I am helpless with is German! The joys of living in a country with 4 official languages (English is NOT one of them).