You mean the livery scheme? You can certainly add one of those: just add one to the end of the livery schemes section in the pakset specific simuconf.tab. You will see the correct format by looking at the others.
As for the acceleration being "very good", as I believe has been discussed on this thread now quite a number of times, such vague information is unusable. I need numerical data for calibration. Please do not keep asking me to adjust the tractive effort based on unusable vague information.
If you have numerical data on actual acceleration rates on the flat with a specific configuration/formation, you can run your own tests in-game to deduce the correct tractive effort by testing to see whether it accelerates to the given speed within the correct number of tiles at 125m/tile based on the source data, and, if it does not, adjust the tractive effort multiplier in the advanced settings dialogue (press the "i" key to access) until it is correct. This multiplier can then be reset in the advanced settings dialogue but multiplied by the tractive effort figures given in the class 800's .dat files. If you do this, you will need to give me full information on the numerical source so that I can verify its accuracy, and also upload the saved game that you used for testing.