All out CAD systems are identicaly configured. All users have all software installed.
Many don't use CADmep all the time but do need the Object Enabler loaded to see objects and prevent consumption of a full license when they're only veiwing.
Please provide an ARX or other methodoloy that defaults to the Object Enaber when opening a drawing and CADmep objects are detected, then unloads the Object Enaber and loads the CADmep application when typing the TAKEOFF command.
The current methodology of specifying the Object Enaber using the "/ld" switch (to force default Object Enalber loading) in the target of the Shortcut only works if you don't need to also specify the ARX for vertical applications like AutoCAD MEP (aecbase.arx) in addtion to ARG profile paths and other shortcut switches as there's a character limit.
Additionally, 2014/2015 will not allow you to manually "Unload" tyhe object enabler DBX if multiple drawings containing CADmep objects are loaded (2014) or even if one drawing w/CADmep objects is loaded (2015).