tips for using the sample editor as a sample editor

i was expecting to just jump in and move the loop points around, or perhaps attenuate the volume, stuff like that. is this stuff possible?

pro tips in this thread anyone? sample editor looks like a cement wall to me, coming from sound forge, wavosaur, reaper, etc.

like how does one set the loop points? how does one make a sample loop? sometimes theres yellow begin and end marks that dont seem to do anything, and sometimes i have no idea how to invoke them. i probably learned these things already but they disappeared from my memory.

have you looked at the documentation?