The whole home limit thing depends on how you have defined them in your ini file. Unless you are using version found in the file R-325Art.zip located in the y?hoo groups files for TurboCnc, they will have to be either home or limit, but not both.
As for the definition of the home postion, this depends on your setup. In MY case, on the X axis I have picked a point that I call X=0 (because of my tooling setup); but the home/limit switch is actually at the table limit and is at X=-2.8". "Home" for any axis can be where YOU define it to be and it may not be 0,0,0 it may be at any convienient position that you choose (or in my case the REFERENCE home is also determined by my limit switches which is a do not exceed in this direction position for axis movement). Notice, I said reference, I can "home" which sets up my machine coordinate refrences and then either jog or G code to my chosen 0 point for any axis.
Hope this helps, but if I have confused you even more (and I probably have), let me know and I will try to help.