update: red tracks are now limited to 80 km/h with 100% penalty reduction, but should be unlimited. I've not tested yellow tracks.
edit: the log is full of errors like this:
Skipping turn speed modification for Bridge_Truss2Lane_Entrance_12_Lane0_TrainTrack: current speed 2097152 is abnormally high (possible overflow)
update: here's the error
Could not find MaxSpeed field in TrainTrackProto
even with the reduction set to 100, turn speed penalty still applies and my trains are braking down to 40km/h on red rails.
would it be possible to make the mod safe for removal? I mean that should probably be possible. just change back the values to normal. then it can be re-configured.