Question on how LED Effects and palettes work and relate

Questions
1

Hello all you !

I’ve been going thru the code to see if i could modify one effect, namely the sinelone_base, that is stolen from FASTLED example.
I’ve just found WLED today, so all my led implementations have been with custom code made by myself.
My two main and preferred effects are adapted from FASTLED examples, but i normally use hue color scheme for them, so i’m very lost on how these effects are built here on WLED.
All i wanted to is to remove the fade_out from sinelone and that each next led would take the next gradient color on the full hue scale.
But i’m lost on the palette color range, intensity and segments, and the reason why that if i set my strip to 50 leds, commenting out the fade_out(SEGMENT.intensity); line i am able to make colors change without those led going black and i get somewhat of a close effect to what i need, but if i set the strip to 600, commenting it out still makes the led fade to black anyways.

https://user-images.githubusercontent.com/33837440/94514625-97412900-0219-11eb-99e1-836a17cb04d0.gif(image larger than 4096KB)

here is the “video” example of what i wanted to achieve.
With fastled i am able to achieve it with this kind of code:

  if (cylon == String(1)) {
      time = millis();
      if (time-timeOld >50) {
        if (z == NUM_LEDS || z >= NUM_LEDS){
        UP= 0;
}
if (z == 0 || z <= 0){
  UP=1;
}
                leds[z] = CHSV(hue++, 255, 255);
                if ( UP == 1){
                z++;
                }
                 if ( UP == 0){
                z--;
                }
                FastLED.show();
                timeOld = time;
        }
    }

Brightness is kind of ignored here as i only set the general brightness once and really don’t feel the need to fiddle with it.

I’m not a pro coder or something like that and i could use some help.
If i use color_wheel function as a replacement for my CHSV object i can get my “hue++” working but i can’t get rid of the fading out of leds.
Can someone give me hand please?
Thank you very much.