MAX_TOUCHES=5 is less than most touch devices, iPad/Android tablets can almost all handle all 10-11 touches. Perhaps a value of 15 would be better?
Note: There is a #define IOS_MAX_TOUCHES_COUNT 10 in CCEAGLView.mm already for this, but multitouch fails on touch 5 in "void GLViewProtocol::handleTouchesBegin" at the code:-
// The touches is more than MAX_TOUCHES ?
if (unusedIndex == -1) {
CCLOG("The touches is more than MAX_TOUCHES, unusedIndex = %d", unusedIndex);
continue;
}