The post processor in MeshCAM is configurable enough that it can support nearly any machine that accepts gcode of some type. I usually recommend that new users try the Mach3 post processor to see if it works as-is. The Mach3 post is fairly generic and frequently works without changes.
If the output from the Mach3 post gives you any errors then please forward them to me and I can try to create a new post that eliminates them.
I've used MeshCAM in the past when I had a Mach3 Mill setup. I have not tried with my Masso Mill but I agree that the generic Mach3 post will most likely work. I suggest reviewing the list of supported G-Codes in the Masso Documentation and comparing them to your code. Masso supports all the primary G&M code commands that Mach3 does so its very likely it will work fine.