The game has been updated to build 662. Here is the change log:
West Somerset Railway
Fixed an instance of a crash when taking over a service that doesn't have aPeninsula Corridor
The map at Burlingame and the poster at Menlo Park have been moved so that they can now be completed by the player.
Resolved an issue whereby the F40PH-2CAT Intro Tutorial could not be completed under certain play conditions.
Fixed the brake squeal and flange squeal audio on the Twin Bay Hopper and the Centerbeam cars so that they are now audible.
Northeast Corridor New York
Revised a number of services (F01-3, F03-3, F05-1 and F08-2) so that they can now be completed.
Fixed the brake squeal and flange squeal audio on all included freight cars so that they are now audible.
Great Western Express
Fixed the brake squeal and flange squeal audio on all included freight cars so that they are now audible.
CSX Heavy Haul & GP40-2 Add-On
Fixed the brake squeal and flange squeal audio on all included freight cars so that they are now audible.
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Minor fixes that should have been caught by in house QA.
Is the GP40-2 still on the old physics?
Approx 550 MB will be downloaded to patch the .pak's. Your download size will vary on the basis of the DLC you own.