There are a few things you'll have to do. Firstly, you'll need to configure the costmaps with either a fake laser scanner (as Lorenzo Riano mentioned) or, I believe, just leave the obstacle_sources empty so that the costmaps assume there are no sensors. I haven't tested the latter, so I'm not sure if the costmaps will actually update if there are no sensors.
Secondly, if you want it to follow a user defined set of x,y points with no planning in between those points, you'll have to write your own BaseGlobalPlanner that just forwards your set of input points to the local planner. If you only need to get to one point at a time, you could try using the carrot_planner for global planning.
Once you have the entire path being output properly, you'll need to tune whichever BaseLocalPlanner you are using (dwa_local_planner, base_local_planner, etc) to prefer following the path over heading directly towards the goal. See Tuning Guide for more info (specifically look for the path_distance_bias and goal_distance_bias parameters)
