nebie, lost in the woods

just getting started with 3D printing, and I build a delta kit from sintron.
the kit is built, and wired...everything works...except I can't seem to get the thing dialed in correctly...

I'm following the instructions, and even managed to get a new Z value uploaded...ONCE...but there it all went to rack and ruin...

my instructions say to dial in my bed height, and subtract value a from the max Z height, but everytime I try to upload the new values, I get an error message....

core.a(main.cpp.o): In function main': C:\Users\Rick\Desktop\Sintron Mini Kossel files\Arduino\hardware\arduino\cores\arduino/main.cpp:5: undefined reference to setup'
C:\Users\Rick\Desktop\Sintron Mini Kossel files\Arduino\hardware\arduino\cores\arduino/main.cpp:15: undefined reference to `loop'

frankly, folks, I haven't a clue what this all means...but Chinese support keeps telling me I have to reload my operating system, or buy a different computer, which is a bit far fetched, I think

everything else works..the bed and the hot end heat up, the g28 and g 29 codes run, etc etc....

I'm running win10, and have an arduino 2556, that was supplied with eh kit...has anyone got any ideas what I'm doing wrong?//I have team viewer if anyone thinks he can help me...

Please attach the sketch you're trying to upload.