TransX Question about TransX with Nonspherical Gravity on

[NOMAD]

I notice that if the the Nonspherical Gravity is set to on,the orbit changes slightly,I had to use a little more fuel to adjust it, so is there any way to predict the orbit in advance so that we can reduce the mid-course correction? I find this in this site http://www.braeunig.us/space/orbmech.htm
I wonder that if this is useful for orbital prediction.
I also find something in this thread http://orbiter-forum.com/showthread.php?t=10129 agentgonzo said that TransX does not model non-spherical gravity sources,so can the TransX model non-spherical gravity sources?
http://orbiter-forum.com/showthread.php?t=10129

 

[agentgonzo]

agentgonzo said that TransX does not model non-spherical gravity sources,so can the TransX model non-spherical gravity sources?

No, it can't.