I have been converting single engines to multiples of four by modifying the unit number in the respective "ace" files. I found that by creating separate "file_name.eng" and "file_name.sd" files (copies can be made of equivalent files found in the "GP38" folder, for example) to go with the "file_name.s" file (in your case, this would be the file exported from gmax) worked every time. Copied files have to be edited in "WordPad" to correct the "GP38" references to "File_name". It may also be necessary to create "Sound" and "Cabview" folders, with appropriate files or aliases. After that, create a dummy activity using the new "File_name". If the engine doesn't appear in the activity editor, then one of the three files does not have all the cross references correct.

If this does not help, please indicate what files you do have in the folder and we can go from there.

Good luck ,

Got it

You need to add a d55.con file into the CONSISTS directory. Here's mine:

SIMISA@@@@@@@@@@JINX0D0t______

Train (
TrainCfg ( D55
Name ( "Deltic 55 (durable)" )
MaxVelocity ( 32.6339 2.31579 )
NextWagonUID ( 1 )
Durability ( 1 )
Engine (
UiD ( 0 )
EngineData ( Deltic55 "Class 55 Deltic" )
)
)
)

You need to create a consist for your Deltic Class 55 before it will appear in the Explore Route locomotive menu. This can be done in the Activity Editor. Open Activity Editor, accept the default route and activity. In the Player's Service section click on new. In the Consists section, click on new. You are now in the Consist Editor. Enter the file and display names (eg: Deltic Class 55). Open the Locomotives (Diesel) menu and select the Deltic. The Deltic appears in the thumbnail box. Drag the thumbnail into the consist box. Click on Save & Exit. In the Player's Service click Cancel. You can now close the Activity Editor, launch MSTS, and drive the Deltic.