Hello,
I find Openproject really complete but I have a few questions because I can't find the information, be precise in your answer and sorry for my English.

Can more than one resource be added to a task.
Can more than one manager be added to a task?
The activity corresponds to a code that should be linked to a cost, how to associate it because I just see costs associated with users.
Each activity code should have their lump sum cost and hourly cost in a project, how to set it.
And how do I set my lump sum or hourly time on an activity code when I log time on my profile page. (check attach file)

I'll stop here for now :)
Copy my question and answer for I correctly associate your answer.

Thanks!