is there detailed manual?
majority of features are obvious and simple to follow, some I am not sure I am able to get them to work
such as audio delay time and buffer,
I do not want to ask about separate things that are actually explained somewhere.

No good manual. But interface quite simple and you can ask me in this forum.

Audio delay working in FFMpeg and MediaCodecs modes.

ok, thank you, this is what I was looking for.
and is there a limit to the buffer? I tried 15 seconds as a try, am not sure if this is possible

For audio delay? Why you need soo large buffer? Usually need 100-300ms.

these are not connected, they were just examples of options that I need.
I was trying with buffer to lower some signal loss due to internet speed.

Options->Timeshift ?

How can I change Favorite list name?