I just played it a little for the first time... All I can say is that it's in an obvious beta. There was a lack of tutorial in-game, so I ran around like an imbecile, lol. I quit out because I sucked too hard.
best way to learn is just get in there and play. I'd never played a second of MW in my life, only took me a day or so to get where I'm at now. Big slow targets, many hitscan weapons = pretty easy to catch on imho
Tutorial may be helpful, but just playing will be more helpful 
<anally retentive>
I might add that the only 'hitscan' (I'm just using this for 'infinite' velocity weapons, I wouldn't know if the devs use a hitscan) weapons in this are lasers, everything else is projectile based hence you have to lead targets that are a long distance away with a machine gun, AC, PPC or gauss rifles.
</anally retentive>
this is true... but even those require little lead
Most lead required is vs aeros, most mechs are too slow to need much. My standard loadout is Shadowcat Prime, 3MBL and 1 gauss... and my starting mech is always Raven C with the PPC, so I know quite well how easy even those are 
The only reason I can think of for lasers requiring lead is lag, of course for both beam and pulse lasers you have to track them (for maximum damage potential), but certainly not shoot in front of the target.
Yeah, even though I play BA a lot, if I absolutely must kill a mech the easy way I will find something with a gauss rifle on it.
Usually go Uller A, Shadowcat Prime, Demolisher A, Madcat MKII Prime.
And if I go Harasser I'm either B or C, C is pretty much for anti air purposes, I love nailing aircraft with the light gauss, B is for when I want to shoot arms off light mechs in early games or want to kill BA's with minimal effort. Could say for most of my game I'm dealing with projectile velocities except for the Harasser B.
