I have a question regarding machine coordinate system as it relates to my CMM.  I was recently thrown into learning and programming our CMM so what I have is what was here when I was given the task of programming.  The attached picture shows how our table is currently setup.  The very bottom of the picture is the front of the machine or the operator side.  The gentlemen that was programming before me (now retired) said we always needed to rotate 90 degrees at the beginning of each program so the "X" was going right to left and the "Y" was forward and back.  This is how our CAD system is setup as well as our programmable mills so that's why he always changed it.  Are CMM's typically setup the way the picture shows?  If so, why be different than the CAD world?  Did someone just setup our machine wrong and this isn't normal?  Last question, is it a big deal to change how the machine sees the "X & Y"?  I messed around switching the axis and that didn't seem like the right approach.  Any help would be appreciated.  

Just trying to get everything setup correctly before I start programming stuff offline using fixtures.  Thanks for your thoughts!