That looks like a guide drawn by ADE to show the fillet for connecting taxi links. As I recall this is going to stay put. You should be able to control what is shown in sim via the taxi link properties such as unchecking the center line. Please test this. If you are unchecking the center line and it still shows in sim then that is another problem
Taxiway paths do not show any center or edge lines when you uncheck them. If that does not work, add a node to the edge of the taxiway. But most probable is that you still have some taxipath links with edge lines checked.
If you double click on the taxipath you should see this screen. Change the Right Edge and Left Edge to NONE. Save then compile and place new EGSS_ADEX.xxx.bgl into your addon scenery Scenery folder for your airport. If you are still getting the lines then you have a duplicate EGSS.bgl file or you didn't place the new file correctly. This method is for FSX. I'm not sure about P3D.