I have prepared a savegame using pak128.CS (and a few addons). Notable trains are:
- Train (18) lead by class 556 Stokr: this is usual steam engine with tender. Bidirectional=0 (both engine and tender), constraint[next/prev] between engine and tender. Turnaround time 6 minutes, reversal is OK. One of the cars (csd_aba) has two parts overlapping. It behaves a bit funny when reversed (see when it takes corners), but that is a minor problem
- Train (19) lead by class TL 659 Turbinka: this is an experimental turbine loco, which due to high fuel consumption needed an extra tank waggon attached. So it is constrained in same way as steam tender engine 556, but is bidirectional (both engine and tender), turnaround 2 minutes, reversal OK. Although this engine does not need turning on turntable, it needs more complicated shunting, so a longer turnaround time might be reasonable. But this was just a prototype, and is not expected to be used too much so there's no need to make special exemption just for this one. (and may be fixed by setting it non bidirectional). However when I used this engine with British mk2 coaches, where rear and front brake cars are defined, it did some funny rearrangements of the train, like class 698 below.
- Train (20) lead by class T 698 Kokakola: This engine consists of two parts. If set as non-bidirectional, the engine reverses nicely (although it takes long time), but also it takes the first waggon (csd_wlab blue) to the front of the train. If set as bidirectional, it reverses quickly, but the unit is spit and recombined with cabs facing each other. And the problem with front wagon remains.
- Train (

railbus class CD_811. The engine and trailers have normal hook & screw coupling, but are constrained with similar vehicles due to remote control of doors and rear engine. The front 811-1 and rear 811-2 engine are in real world identical, but I had to code the rear one as can_lead_from_rear=1, to get the desired behavior. (no rearranging, 1 minute turnaround). Again the middle cars are pax+mail combo which looks funny when reversed)
- Train (11) railbus class ZD_810. front engine coded as can lead from rear. Turnaround OK (2 minutes, as it has to shunt). Train arrangement OK. I think there used to be problem with such combination, but now it is OK. Thus the train 8 could be recoded to have CLFR on both ends - as does e.g train 13 and 14.
- Train (10) regionova trio 814, this is a fixed DMU of three cars, but is capable of pulling normal trailers. It is bidirectional, with the last unit CLFR=1. If running alone, it works fine, but with a trailer it gets rearranged with cabs inside. This should behave the same way as swedish Dm3 (three-part electric loco for heavy freight).
pakset:
http://list.extended.simutrans.org/pak128.CS-Ex.zipaddons:
http://list.extended.simutrans.org/csd_y_extended.paksave:
http://list.extended.simutrans.org/debug-saves/twin-engine.sveSo, only trains 20 (kokakola) and 10 (regionova) need a fix
Do not rotate the map - it will segfault. :-(