MARLIN 2018 is a disaster of errors and warnings.

Using Arduino IDE 1.x
1

Marlin (c) 2011-2018 MarlinFirmware is FULL of errors on opening and compiling. One error mistakenly finds a "-" instead of an "x". Another error says "BYTE" is no longer supported, and there are dozens of "BYTE"ipreventing compiling.
That's on top of dozens of warnings. WTF? I thought Marlin was bug free! I'm a newbie and don't know C++. I ha
ve absolutely no idea what to do to get my homemade 3D printer up and running using MARLIN.

HELP, please.

2

There will be many versions of Marlin marked "Marlin (c) 2011-2018 MarlinFirmware". That's not a useful way to describe which version you're using.

You can get the official Marlin releases here:

kpgreskAR:
WTF? I thought Marlin was bug free!

I'm sure they'll be happy to provide you a refund for the full purchase price of Marlin.