Downloaded Locomotives on TS2014

How do you get downloaded locomotives and cars to show up on the available list of locomotives, cars & consists for use in Editing a Scenario?
Does it only display locomotives acquired through Steam?
Can Car Consists be Modified for the Existing Scenarios?
Thankyou,
DaveKfromUP
Does it only display locomotives acquired through Steam?
Can Car Consists be Modified for the Existing Scenarios?





Thankyou,
DaveKfromUP