Here is^B^Bwas 2.0.1 alpha 41 pre 6, which includes path-based signalling.
PLEASE read the instruction below before trying it, or your train drivers will die, and your passengers. These are not idle threats, I mean it!
Usage:
- All pre-signals, exit signals or combo signals function as path-based signalling signals now by default (disable with a miscmods setting)
- Whether these signals are red or green does not matter for whether the train can pass them, except that if the train can't find a route to its destination, it will wait at a red signal, but not a green one
- The train can pass a signal, if it finds a route past the signal leading out of the signal block or to its destination. It won't find routes that end at red two-way signals.
- Because track pieces are reserved only if a train approaches or passes such a signal, either all or no signals leading to any signal block must be pre/exit/combo signals. Therefore if any signals in a block are PBS signals, all of them will be converted to PBS.
- The next signal from any pre/exit/combo signal must be less than 64 tiles or 7 junction pieces away (that's a limitation of TTD's pathfinding)
- The "reverse" button should be safe to use in alpha 41 pre 4. If it causes problems, please report them.
- Depots work fine in pre 5 and 6.
- If track pieces are stuck at "reserved" (dark), try forcing a train to run over them, or bulldoze the tile and rebuild.
There's also a demo savegame, which I've saved just before a situation that shows off this feature. Just watch Carnley station for a few minutes and be amazed!
Have fun!