I'd recommend using the arch wiki for troubleshooting your problems. They have some of the most complete documentation of all things linux I've ever found. The fixes will mostly be applicable to other distros.

1) For the yellow tint the only thing I can think of using is xrandr, and almost every graphical enviroment has a front-end for it. If not you can run xrandr in the terminal to list the screens, and use 'sudo xrandr --output <screen name> --gamma r:g:b' to set the gamma correction. As for the trackpoint you should probably read the manual page for xinput. Type "man xinput" to view it. (reading manual pages is a great way to troubleshoot problems)

2) Sed is a regular expression parser. I'm terrible at regular expressions but the script you've been told to run prints everything from the output of xinput that looks like "id=number". It's kind of unnecessary because the output of xinput is like 10 lines and is very human-readable. You made the right choice by not running some random lines of code before you know what they do.

3) I'd recommend dual-booting, unless you're okay with abandoning those games forever.

Hope I could help.