Dutch Trainset Cargo Extension
The Dutch Trainset Cargo Extension is a NewGRF that adds additional refit possibilities to the wagons of the first Dutch Trainset. This allows the train set to be used with industry sets such as FIRS, PBI and ECS. The extension does not provide any new graphics, so the graphical representation of 'new' cargoes will default to some standard TTD cargo.
Support for new cargoes is built in Dutch Trainset 2.
The extension is only available for OpenTTD, and can be downloaded form the ingame Online Content. If want to install manually, you can get the set from here.