The only thing that can actually even pass for a quitar is POWER. Thats about it... Flslayer sucks
Slayer is great, you just have to use it right. Sure it isn't going to produce Iron Maiden lead guitars, but thats not what it is about. No guitar simulator will be able to sound like every single guitar out there, and if you want want it sound good, you are going to have to put in the effort. Use FX (Especially EQ), tweak the notes, learn about the slides. Slayer is just like any other synth - only useful sometimes, and you will have to put in some effort to make it sound good. It can do some awesome backing guitar work, and is unbelivably good for those situations where you want a cheap sounding guitar. It is also for those situations where you want somethign vaugely guitar sounding, but no guitar could possibly do stuff like that.
As for tutorials... ummm. Just play around with it, look at the help file, see how it works, particullarly the different input modes (Solo fixed, solo dynamic, strumming, etc).
As for your question about holding, I tend to leave hold off, and just extend the note if I want it to go on for a while. Or, if I want that squeal, I leave it on hold, then mute the channel when I don't want the squeal, and unmute when I do.
Well, there is a panic button, just in case sounds do go on forever... fogoten what it is though. As for why they are doing it forever.. curious. Do your pattens go on for ever? If the sound is continuing after the note has stopped, then it sounds like a problem with release - check your envolopes. Oh! The other thing is, you might have it set to play the pattern, not the song, where it just repeats the current pattern. Fix this by clicking on the song LED just next to the play button.
If none of this helps, I've probably mis-understood you. Try explaining it again, and I'll try fixing it again.
During the song is goes on forever where the pattern has ended and it plays even when the song is finished. And has anyone heard Fruitydream from FL3? I want remixes of Fruitydream...
And not to be troublesome or anything but if any oc remixers can plz send their flp files so i can learn that would be nice. (Its not like i'm going to steal someone's work.