The narrow gauge locomotive is found on the DLS; It's one of the 30in DM-12s by David111767(<kuid:181672:100483> 30in DM-12 Yellow) It also comes in BN, Grey, and Red liveries. The hoppers are also on DLS(<kuid2:181672:29758:1> 30in Hopper (Brown).
If you have purchased the Eagle River Route please redownload the sessions from your link. A couple of the sessions could not be completed in game due to bugs in TANE, I've since redone the sessions. So please install them and they will overwrite the previous versions!