AFP - What Do These Mean/Do ?

[bloopaloop]

The wiki page for the Audio File Processor plugin (https://lmms.io/wiki/index.php?title=AudioFileProcessor) was last updated Jan. 2015 and seems to be missing some things due to being out of date. So I had some questions about some of the new functions that aren't covered in the wiki page.
1. Next to the cyclic arrows, there is now a button with 2 triangle-ish shapes that are a mirror image of each other. It seems like when this is enabled the sound it affects plays normally and then in reverse. Is that right? If not, what does this button do?
2. In between the knobs that control the start and end of the sound, there is a new knob with a symbol underneath that looks kind of like this: >l< What does this knob control?

Thank you.

[D.Ipsum]

AFP = Audio File Processor

1)
With the cyclic arrow enabled ("enable loop"), the sample will be played from beginning to end, from beginning to end, and from beginning to end as long as a note is played.

The button with the two triangles (the same name : "enable loop") make the same, but the sample will be read from beginning to end, and then from end to beginning, and then from beginning to end, etc. as long as a note is played.

2) The "loopback point" takes effect when one of this two "enable loop" is activated. Load a sample and try to understand (I don't know how to explain).


My explanations are fantastics

[bloopaloop]

I thought your explanations were lovely.
This really helped, thanks.

[D.Ipsum]