Hi James,
I'm sorry I have to report a finding again. I've reproduced this in Simutrans Experimental 9.5 with Pak128.Britain 0.8. but IIRC I've seen it in earlier versions as well.
In this (http://forum.simutrans.com/index.php?topic=6343.0) topic you point out that major rivers do not have the way_constraint_prohibitive set, so any ship ocean-going ships should be able to navigate them. Unfortunately, this function doesn't work, all ocean-going ships will respond that they can't find a route when needing to find a route into a major river.
I hope this helps. If need be I can supply you with a save game.
Kind Regards,
DoR,
thank you for your report. Can you upload a saved game in which you can reproduce this issue?
Hi James,
Well, when I tried to make a reproduction, I couldn't make it work. I get the impression I mistook previous versions or something like that and that there's no problem after all in 9.5. If I do see it, I'll post a save game.
Sorry for the inconvenience. :-[
Don't worry. Thank you for the report in any event :-)