To create context :
goto Tools --> Detect Loops, BO will detect loops if there are any & will suggest the context candidate (something like Sales, Costs that is related to that specific subject area)
Select the suggested candidate & click on create Context. It will map all those joins that are required for say Sales subject area & put it in Sales Context. same with Costs.
So it will avoid the confilcts in path by using Contexts.
This Auto Detection works in most of the times....but not always.   _{Your Comment}