1999 Jeep Wrangler "shifter pop gear under acceleration" Questions

...gear occasionally slips to neutral I have a '99 wrangler with the 4cyl engine and 5-speed manual trans. First I'd like to point out that the shifter itself isn't stock. It was like this when I bought ...

...shifter moving a good amount. i dont know much about mechanics but im sure thats not good. also if i punch it from a stand still or take off too hard on a hill it will pop out of gear. whats could be ...

...shifter in to reverse. As you let off, it'll eventually pop right in to gear. u have to open the throttle then oilling and greesing throttle and if accidently probelm occurs then u have to therew the ...