I need some serious help

[LuckyImperial]

Nick,

They have you compiling a Marlin version with Arduino IDE version 1.6, which is a terrible idea. It's known to be plagued with issues. Good news is I've got a 0.92.5 (latest) Repetier-Firmware for you to upload and try.

Here's what you need:

Your firmware (I made this using Repetier Firmware Configurator):
https://drive.google.com/open?id=0B1...GVwVE9LT2ZTcXM

The latest version of Repetier-Host:
http://download.repetier.com/files/h...Host_1_5_6.exe

And Arduino IDE 1.0.5 (even though Repetier-Firmware can be compiled with IDE 1.6):
http://arduino.googlecode.com/files/...r2-windows.exe

Before you upload the firmware do this in the Arduino IDE:
File -> Examples -> EEPROM -> eeprom clear
Then upload that sketch. It's smart to clear out your eeprom before you upload any new firmware.

Please be careful when you do your first movements with the new Firmware. Hover over that power switch. I'd be really surprised if I got EVERY setting right the first time, but hey, maybe. Also...you can now use Repetier-Host to do everything. It has a manual control tab that you can send G-Code and movements through. Unlike Pronterface though, commands are qued until they complete. So if you send gcode to bring your hot end up to temp, then other commands wont go through until the hot end reaches the set temperature.