There's no reason for the program to allow you to enter LSA if you enter the ICL and ECL.
That's because LSA is simply (ICL + ECL) / 2.
Example: A cam with 104 ICL and 108 LSA will always have an ECL of 112. So a cam with an ICL of 106 and and ECL of 118 will have an LSA of 112. That's just the way the math works out.
