Don't you think NbrDiv should be an integer ?

SlidingSurface3D/rfpm_common.pro

@@ -8,7 +8,7 @@ If(lc <= 0)
 EndIf
 
 // Number of elements on the sliding surface in rotation direction
-NbrDiv = 100*mm/lc;
+NbrDiv = Floor[100*mm/lc];
 
 ModelAngleMin = 0. ;
 ModelAngleMax = 60. ;