Here you can read the Q&A history.
To get new community support please go to GitHub discussions (KnowageLabs/Knowage-Server · Discussions · GitHub).
We do not have such document at the moment. Please refer to the community documentation available here:
http://download.forge.ow2.org/knowage/Knowage_6.x_CE_Manual.pdf
Anyway, we are in the process of releasing a brand new documentation online, but it will take a while (end of June probably).