My ideal weight is 170 lbs but I'm training to get to 181 by end of summer (buddy and I are using similar charts:-) ). I'm at 195 lbs now, so still stocky. My 1 rep max wasn't 135 at first, but it was the max weight I could do 10 reps of. At my weight now, the advanced percentile is way higher than 315. It's 387 according to that chart. The 315 lbs set takes all my effort. If I don't eat right, sleep well the night before, and am not mentally ready, I might fail after about 4 or 5 reps. I've gone up to 330 lbs but then my form just sucks and I'm not squatting deep enough. I imagine if I want to get up to 365 lbs it'll probably take me another year. All that said I'm happy with my level on squats now. I'm not as strong on dead lifts (flexibility problems still) and I'd rather focus my effort there. I've been stuck doing Romanian dead lifts until I sort out those flexibility issues and can get my form right.

My buddy who is training me happens to be an engineer who loves these charts and reads a lot about training. He immediately identified my natural strength on the squats but pointed out that my flexibility was absolutely atrocious (sitting all day as a programmer, who'da thunk!). So he forbid me from doing back squats at first. I focussed instead on doing lunges, lots of stretching, and then we eased into doing body weight squats and dumb bell squats. He also had me strengthening my core as much as possible so it'd be ready for squatting.

Other than that, I have a nice natural ability to put on muscle. That's never been a problem. My problem is as the muscle packs on, so does the fat. A lot of my progress is attributable to my training buddy though. He really pushes me and on days when I work out alone, I don't nearly get as good of a workout. It also helps that we've both got the same ideal body weight (although his problem is he's naturally underweight). So we don't want to fall too far behind the other in our weak exercises. We're both too lazy to want to keep moving plates back and forth onto bars in between our sets :-)

UPDATE: just saw this part of your post
How about many rep's per set and set per session did you do? And how pound increment did you add for each week?

After the first couple of newbie sessions of squatting, I could do 6-8 reps at 185 lbs. We would do 4 sets of squats right at the beginning of our workout. First set involved 6 warmup body weight squats. Set 2: 6-8 135 lbs. Set 3: 6-8 155 lbs. Set 4: 6-8 185 lbs. We'd only do squats once a week. Only in the past month have I increased squats to a once or twice a week exercise. If you aren't hurting (at first) or stiff (later) for the next couple of days after squatting, you're probably not pushing your max weight and you have some sort of mental block. At first the long rest left us completely fresh for the next workout.

The way we train is that we don't move up until we can get a high rep set at our previous max weight. So even though I think I can only do 6-8 going into that last set, if I can push myself to do 12-15, I will. This is where a gym buddy comes in handy. They'll know if you're sandbagging and will tell you to push out two more reps. If I hit this target, we move up a weight class, which at first meant throwing another 30 lbs on there to 215 lbs. I stuck at 215-225 for a while. Then we jumped up to 275 which was shocking after about 2 months at 225. I stuck at 275 for another couple of months and then we started putting on 10 lbs here and there, until I could get to 300. That was a big psychological double-edge sword. It felt like a hell of a lot of weight but it felt good being able to do that. A couple of weeks of 300 was enough for me to get to 315. I've stayed there and really focussed on improving my form and depth.

Right now we're doing 4 sets as described above, and then on the 5th set we drop down to whatever weight we can handle 15-20 reps of. For me right now, that's 225. After that last set I'm about ready to pass out, it's pretty exhausting.

I dunno, sounds pretty chaotic :-) But we like to change it up. We're constantly contradicting ourselves, one week going for low rep high weight and the next going for high rep moderate weight sets.