After studying the lay out of existing pak64 boats, I set sail on my voyage of painting this vehicle type. I've got absolutely no idea if it is any good. I'm proud enough to share it here but that's as far as I go!
Images attached of my version and the Uber Boat Thames Clipper can be found here:
This is more or less to scale; however Simutrans pak64 uses a much smaller scale for ships. In Simutrans scale, this is more like a fast ocean katamaran.
I do not have the impression that the various ships in pak64 are on the same scale. Especially the diagonal images. Maybe big ships must be compressed then for technical reasons, but still.
However, I do get the impression of something perhaps a bit larger. The page you link to, lacks information about size, so I'm not sure exactly how big it is supposed to be.
View four and eight seems to be straight from the side, which would look like has capsized in the game, where we see the view from slightly above. There may be other vehicles in pak64 that are similarly drawn from the side, but they are much narrower, so the difference is not as apparent.
Thank you both! I will readjust the scale and also skew the side on images more :)