[adenty9]

I found out I can edit .strm files to play playlists, just by linking directly to the file (eg, C:\...\AppData\Roaming\XBMC\userdata\playlists\video\AmericanExperience.m3u).

This is great because I can collect episodes from a show on the PBS addon, or the youtube addon, and add the strms to my TV shows library, and it'll load the show info, and all the other perks of having it a part of your library, instead of just a plain old playlist. And it loads the playlist and plays fine when I do it this way.

But when I try to link to a particular section within the addon, in this case a show (eg, plugin://plugin.video.pbs/?mode=0&name=Charlie%20Rose%3a%20The%20Week&program_id=376978), it loads the addon like its about to play, but then says "Can't play next item in list".

I have almost no coding skills, but I'm guessing it's because it's attempting to play the top item, like it would with a playlist. But, unlike a playlist, the top item is not an actual item, but rather it's the "go back" or [< ..] option.

I may be wrong about this. Let me know. But in case I'm right, I'm wondering if there's something simple I can add to the path (plugin://plugin.video.pbs/?mode=0&name=Charlie%20Rose%3a%20The%20Week&program_id=376978) to make it skip the first item...?

[learningit]

The url that you give for a particular section does not resolve to a playable item, so the player doesn't have anything to play. What that url does do is: create a directory of playable items for the given PBS program. It can be added as a favourite, but not played from a .strm. The "Can't play next item in list" is because there isn't a playable item in the list.
If you add the url or heading as a favourite, when you click on it from favourites and it will display the videos available for that PBS program. You can pull up the context menu ('c' on the keyboard) and select 'play from here' on the first item you want to play and it will create a playlist and play it. The play list is accessible while it is playing by pressing 'c' again. While the playlist is displayed, you can save it by pressing the left arrow key and selecting 'save'.
As best as I can see in addon code, there is no 'auto-play' of a current playlist for a given PBS program which I think is what you're trying to achieve, although I could have missed something.