Also, Flame Hyenard? This is what the 4 options actually mean with examples on which should be used when:
1st option :The original song naturally loops
If the original song loops naturally, i.e. pretty much 99% of all video game music, then select this. For example, a boss theme from some game, or a general stage BGM, menu theme etc., would use this.
NOTE: The start and end loop points do not make any difference to the fact it's a normal looping song, so, whether you start at 4 seconds, or 50 seconds, if the song originally loops, then this is the option you should choose.
2nd option :The original song does not naturally loop, but the Brstm does
If the original song ends, or fades out, for example, an OC remix, or maybe a soundtrack from a movie or TV theme, or something like that, or just a normal song (let's say a Michael Jackson song, or something like that), and you have made it loop non-stop, then choose this option.
3rd option :The original song does not naturally loop, and the Brstm reaches the end and starts over
This is similar to the above option, however there is no custom loop, that is, after the song fades out or whatever, it will start up again from the very beginning.
4th option :This song does not loop
This is simply for maybe victory themes, or generally short jingles, but if you have a non-looping title theme or something, then you'd use this option, if the actual BRSTM is not set to loop at all.