I just realized, that I have an unused Steam key for the 'Train Simulator - Burlington Northern F45 Add-on'.
I bought the add-on several years ago at uk.gamersgate.com, after all of the BNSF related add-ons was changed to US only content.
There were no mention of US only content on the uk.gamersgate.com page, so I gave it a go, but without any luck, I couldn't activate the code.
The steam key is not activated yet, so it should be ok. If someone wants this add-on, just reply to this thread.
The first user that replies to this thread will get a PM with the key.
Remember, that you have to be located in The US to use the key.
The best regards Claus