BL-USBMACH-2.1 Limit and Homing Wiring

Beginner here. I am recently coming to the end of an 8 year project of completing my DIY CNC router. However I am having trouble finding any good instructions on wiring the limit and home switches to my BOB, and then the set up of them in Mach 3. I am using a BL-USBMACH-2.1 break out board, I know its cheap but its what I can afford.
Was wondering if anyone would be willing give a detailed diagram and/or description of how all switches should be wired and how to set them up in Mach3?

Also....

I cut my first piece with this new DIY CNC router and ran into a snag that I am unable to diagnose. The piece was designed and tool paths were created in Fusion360 and ran on Mach3. 360 tools paths when simulated showed clean sailing. When put into Mach3 after zeroing all coordinates on the front top corner of the work piece, when the code began to run Mach3 plunged the z-axis halfway through the material and moved to the starting spot of the cut and then returned the z-axis to the correct coords and cut the piece. When completed the z-axis plunged again to the center of the piece and returned to the soft limits again cutting through the middle of the piece. Can anyone explain why this did this? Again I am a newbie and apologize for any of my ignorance.

Thanks