So how long can a code be?
Reasonable. If you dump 10k lines on us nobody will look at it. Only post the necessary parts which you want to be reviewed. Normally this is done on class- or function-level, meaning you post the whole class/function you want to be reviewed and maybe the direct relatives (classes/functions which are directly effected by this).
what are a few things to be looked into when I ask questions or put my code for review here?
Explain explain explain...explain what the code does, what it is supposed to do, why you think it needs review.
Is there anything programmers who review the code expect from someone who puts their code to get reviewed?
Feedback in all variants and colors.