Hi again
I have made extensive use of this rule on the built in ECML route and it works fine for me.
The first thing to do is to write down the junction names in the correct order for the path that you are going to enter so that you can refer to this list when you are entering the path into the rule.
Once you have added the Path rule to your session, click on edit which will open the box which has one entry "add new yard". Click on this and it changes to show a grey button with "yard 1" at the side of it. Click on "yard 1" and rename it to whatever you want. I normally set up a yard for each town or yard that the train passes through. On the ECML for instance one of my yards is called Doncaster which has all the paths through Doncaster station in both directions added to it.
If you then click on the grey button it will open another page with "yard menu" at the top which will return you to the previous page. The second item is "add new path" which when clicked will open another page with a grey button on it. Click on the grey button and it will expand to show the page where you can edit the path. The first thing to do is to edit the path name to something meaningful. In the Doncaster yard mentioned above it might be "Dcr Up Main Through" or "Dcr Up Main to P3" for example. Once you've done that, click on the "add new junction" line and it will open a box where you can select the first junction on the path. Once you've selected the junction you can set it's direction using one of the three buttons displayed on the right hand side. Continue to add junctions until all the path has been entered. You now need to set a release for the path which is done at the bottom by clicking on one of the icons for junction, trackmark or trigger. This will open up a box where you can select the appropriate item name. I normally use the last junction on the path which clears all the junctions immediately the train has completed the path. It may be that another train is waiting to use one or more of the junctions for another path.
Once you've added the paths that you require then you need to close the path rule and open "Driver Command". Put ticks against the "Autopilot" and "Path Command" driver commands and then close it down. When building up the schedule for a driver you will see "Path command" and when you click on it you should see a list of your yards and, leading from each yard, you should see the individual paths for you to choose from. After selecting the path, you then need to click on the "Autopilot command and tell the train to either drive or drive to a trackmark.
If the route that you are using is quite large then I would advise adding paths as you need them rather than trying to add all the paths at once. I use the rule in conjunction with the Schedule library so that it is much easier to add the commands for any other trains using the path. You can build paths up in the driver schedule before adding the autopilot command e.g. Path A, Path B, Path C, Autopilot.
_mutton_ has a website here
http://www.mutton.de/trainz/pathrule/ which has information on the rule.
Hopefully this will get you started but if you have any further problems, post back with the issue and I'll help further if I can.
Regards
Brian