The DMU DB BR 643.2 which drives on Schnellfahrstrecke Köln-Aachen has 2 cars and is at the ends of the unit painted in blue: This train is also driving on the RB20, which drives on the sections Aachen - Stolberg (every 30 Minutes) and Langerwehe - Düren (every 60 Minutes). Between Stolberg and langerwehe, the trains drive on a seperate route next to the main line. There may be other lines between Köln and Düren where this train drives. Now a picture from the inside of the train: (This may be another 643 than the train from the euregiobahn.) If licensing is a problem because of the "euregiobahn", you may just make a train in the DB-Livery. The euregiobahn isn't a company, it's just a brand. The BR 643.2 would add a lot traffic to Schnellfahrstrecke Köln-Aachen and would be the first german DMU.
This is a great suggestion not only is the train perfect but also the branchline and it finally makes Eilendorf a useable stop
I live in Aachen and would be happy about an entire addon "Euregiobahn". The entire "Ringbahn" from Aachen Hbf via Herzogenrath and Alsdorf to Stolberg Hbf. Continue to Stolberg Altstadt and of course the valley railway with connection to the coal-fired power station "Eschweiler-Weißweiler". This could be a 15 Euro addon, like the TS extension of the s-bahn Köln to Cologne-Bonn Airport via Troisdorf.
drnicktgm#1259 that is a problem, I never saw this route in TSW yet. The BR 643.2 has a very good place in TSW2: on Köln-Aachen between Aachen and Stolberg and Langerwehe and Düren. I don't know any route (a route, not a signle station) in TSW where we can use the BR 644 with realism.