I'm a new user of PI and I'm having some problems trying to put in the same plot two differente variables and, at the same time, a fixed picture (a columns graphic).
This picture ilustrates the problem: 
Depending on the location of the operation point, the crew inside control room knows if they're working in a safe (green) or unsafe region (red area in the graphic) and can take actions in order to deslocate the point (acting on variable 1 or variable 2, depending on the resources they have) to the safe region.
Which tool in ProcessBook is the best one to create this plot? I tried XY Plot, but I don't know how to put the fixed columns and plot the operation point at the same time.
Do I have to develop a solution using VB and the resources offered by PI?
Thanks for your support!