Question:

How do I change the default icon and program that .sgn files open with to OpenRoads SignCAD?

Answer:

In File Explorer, right click on a .sgn file and select Open With>Choose Another App. Select OpenRoads SignCAD, check the box that says "Always use this app to open .sgn files." and press OK.

NOTE: If OpenRoads SignCAD is not available for selection, then pick More apps>Look for another app on this PC and browse to the C:\OpenRoads SignCAD folder. Select the OpenRoads_SignCAD.exe and press Open. Select OpenRoads SignCAD, check the box that says "Always use this app to open .sgn files." and press OK.