GREAT progress on the lifts! Hard to tell on the bodyweight without seeing pics, but it seems you could have gained just a bit more in six months. Just remember that when your lifts start to stall, eat more and they'll start moving up again.
Liquid chalk is more expensive and doesn't work as well as block chalk. Just stuff a block in a ziploc and rub it on your hands. Most of the time nobody will say anything as long as you don't make a mess. $12 will get enough to last a very long time.
Sounds like your upper back isn't tight enough on squats. Take a little wider grip (it may take a few times to find a happy spot) and flex your upper back tight. You'll find that the bigger you get, the wider your grip will have to be. As your back muscles get thicker, they hold the bar further off your spine, and there's not as much 'room' for your forearms.