Check the log in the bottom window of the BP Editor after attempting the export. On your screenshot it says it didn't complete the export due to errors, and usually (or even always?) these errors are specified somewhere in the log. Could be anything like a bad texture or a missing dependent file.
Regarding the missing bogie blueprints: these are crucial and 100% needed for the locomotive to function. You *can* reference them from another locomotive but only if the loco's (the actual 3D model's, not the prototype's) wheel sets are absolutely identical (same dimensions, positions and offsets of wheels and axles).
Read on here for more information:
http://railworkswiki.com/tiki-index.php ... set+Editorhttp://railworkswiki.com/tiki-index.php ... e%20Manual