The problem is that, unless you tell the panel otherwise, your geometry is going to extrude from the face of your panel relative to some calculated normal of the individual panel, and not have any relationship to it's neighbors. What you might want is a shared edge, which means a shared vector based on the edge condition, not the overall panel condition. In section, the difference is like this:
This video shows how to get the relationship that creates a seamless edge. The principle is that you want to build your geometry based on the planes defined by points, rather than on the overall plane of the panel.