Marlin firmware not functioning properly

I've recently put my delta bot together and when I uploaded the software that the maker of my kit email me the firmware doesnt work smooth like i've seen in videos. It'll home correctly but the major problem is that the printer thinks the print bed is bigger than it is and also the overall firmware tricks the printer into going outside of its axis allowing it to crash. I have tried adjusting the print bed radius but that led to nothing. Its hard to calibrate this machine because when i home it I see that the Z axis shows that it is at Z893 then it'll show that its at Z(290) which is the default in the manual_z_home_position. So my guess is that something is set at the max I guess. I have attached the files that were not in the original marlin firmware. So with that being said can someone help me by taking a glimpse?

I will try to help, but it looks really messed up.

First, you need to make sure that you have the right measurements in. Measure the smooth rod, diagonal rod, carriage, bed, effector, ....everything. Make sure the numbers match. Google each item to find what it is, and get as close as you can.

Chances are, that they have the wrong number.

Secondly, make sure the bed is centered. The kit I got, you could not center the bed between the xyand z. And this caused the head to try to reach a part of the bed that was not there.

And recheck every screw.