why do I get a message about material thickness not working with cuts
I using standard easel not pro
Can you quote the error or get a screenshot?
Only I can think of is you have set material thickness to be less than what you previously have set carve depth to.
(Unless there is a bug / anomaly appearing)
Yup, a screen shot would be nice 
Change your depth of cuts in in your work space to be shallower than the work piece you intend to carve. I have gotten this before if I start out with a material depth of .5 After I set the project and realize I am working with 1/4" materiel I will get this message when trying to make the material thinner. Basically I have cuts specified to be deeper than 1/4" material thickness. Hope that makes sense. Steve