I read this with interest and would like to make what are intended as constructive remarks
 

kevinwal
I too have the mysterious dotted automation lines appearing willy-nilly well past the end of the song, and I've not been able to discern exactly why they get put there. Was it something I inadvertently caused to happen? I do a lot of cutting and pasting during arrange sessions and I suspect it has something to do with that but I don't know for sure. I would love to know what the "rules" are for these things.

 
Whenever you have an envelope in a track, there will always be a solid dotted line after the last node. So it would seem that what you're seeing is normal and intended
 

As to the end-of-song marker, it would be useful for me. I often record bits in a non-linear way and place them well after the body of the song, then use them when I'm ready. I often end up not using these bits in the song I'm working on for whatever reason, but like them enough to not want to lose them. Incidentally, I'd love to have the ability to put these in some kind of "idea bag" in a way that's well integrated in the workflow.

 
Just a thought, put all of your little snippets into their own folder with a suitable name. Move them to wherever you want

Anyway, I often only want to render the tune without the music blocks at the end, and an end-of-song marker would be useful to easily exclude them. Yes I know I can highlight the timeline to render only the parts I want, but that often results in many more clicks because I tend to render a lot to test the sound quality at various mp3 quality levels. Also, I'm often zoomed in, so to select the timeline part with any accuracy I usually have to adjust the zoom level first, then select the timeline portion. Not a big deal, but quite a few clicks that an end-of-song marker would tend to substantially reduce.

A very easy way to overcome this is to set up 2 different screensets.
 
Just a few ideas which you might find useful

After lots of editing I often see lots of dotted lines both before and after solid lines in volume automation. Once I start seeing those, if I simply select all tracks and render there's usually (but not always) a lot of silence padded onto the end of the rendered output, often as much as twice or more the length of the song itself. I haven't tried to put together a concrete set of steps that will reproduce this behavior so I can't say for sure that I did something to trigger the additional envelope data, or even if this is simply a logical result of the things I did during the edit session.
 
I'm not sure if this is related to the behavior you're seeing, Craig, but it's an additional data point and may just in fact be noise.
 
 

Bristol_Jonesey
I read this with interest and would like to make what are intended as constructive remarks
 

kevinwal
I too have the mysterious dotted automation lines appearing willy-nilly well past the end of the song, and I've not been able to discern exactly why they get put there. Was it something I inadvertently caused to happen? I do a lot of cutting and pasting during arrange sessions and I suspect it has something to do with that but I don't know for sure. I would love to know what the "rules" are for these things.

 
Whenever you have an envelope in a track, there will always be a solid dotted line after the last node. So it would seem that what you're seeing is normal and intended
 

As to the end-of-song marker, it would be useful for me. I often record bits in a non-linear way and place them well after the body of the song, then use them when I'm ready. I often end up not using these bits in the song I'm working on for whatever reason, but like them enough to not want to lose them. Incidentally, I'd love to have the ability to put these in some kind of "idea bag" in a way that's well integrated in the workflow.

 
Just a thought, put all of your little snippets into their own folder with a suitable name. Move them to wherever you want

Anyway, I often only want to render the tune without the music blocks at the end, and an end-of-song marker would be useful to easily exclude them. Yes I know I can highlight the timeline to render only the parts I want, but that often results in many more clicks because I tend to render a lot to test the sound quality at various mp3 quality levels. Also, I'm often zoomed in, so to select the timeline part with any accuracy I usually have to adjust the zoom level first, then select the timeline portion. Not a big deal, but quite a few clicks that an end-of-song marker would tend to substantially reduce.

A very easy way to overcome this is to set up 2 different screensets.
 
Just a few ideas which you might find useful

Thanks for the ideas, I'll have to look into the idea of screensets. I confess that I haven't made much use of that feature so it's no surprise to me that there might indeed be a way to make use of them for this. In the end, though, I think I'd like a project-independent way to capture these blocks of music. I though about just making a separate project for them so that I had one place to go to browse them for ideas but the thought of managing the various plugins I tend to use has always deterred me. An idea for another thread though. Thanks!