To force Advance Steel 2013 to always start with AutoCAD 2013, you need to add a new parameter to the program shortcut, in the "Target" field.
This parameter has the following format : /AcadVer R19.0\ACAD-B001:407.
The ACAD-B001:407 string is not common between different AutoCAD 2013 installations (it may vary based on language installation and package distribution), therefore you will need to identify which AutoCAD version do you have installed.
To do this, open "Windows Registry Editor" (type regedit in Windows Start menu), and browse to the registry : HKEY_CURRENT_USER\Software\Autodesk\AutoCAD\R19.0. Inside this folder you will have one or multiple folders with the names ACAD-B followed by numbers. If you have only one (like in this case, ACAD-B001:407), then you can use it in the shortcut parameter format. But, if you have multiple AutoCAD 2013 installations, then you need to identify which one is the one you want to use. You can do this by clicking on the respective folder, and checking in the right side if the paths for the various registries here target the folder where your AutoCAD 2013 is installed.
