Thank you Carlo and Shelly,
 
I think the warning message is that "rmax is greater than the distance to the most distant atom"  .  My cluster size I put into ATOMS the last time I ran this is 5.5.  The message then says rmax,ratx  5.5000   5.09117.
(My experimental data goes to R = 6.) No matter what cluster size I choose I get the same warning with ratx less than rmax by a small amount. I have tried several cluster sizes and always get the same warning.
 
Sincerely,
 
Doug