For some reason I am getting a negative number in this field when it should never be >0. Below is the exact calc I am using. I thought it would stop at 0 but getting a negative number. What am I doing wrong?

Min ( Max ( 0 ; l_ff_roll2_ft - l_ff_roll2_m_diff) ;l_ff_adult - l_ff_roll1_a - l_c_ff_roll1_adj; )

I am going to assume that your:

l_ff_adult - l_ff_roll1_a - l_c_ff_roll1_adj is producing a negative number.

In a specific scenario yes. However I want the result just should never drop below zero but can never exceed the fields shown.

Well then shouldnt it just be?:

Max ( 0 ; l_ff_roll2_ft - l_ff_roll2_m_diff; l_ff_adult - l_ff_roll1_a - l_c_ff_roll1_adj )

Sorry I am not following your request here...

I want the result just should never drop below zero but can never exceed the fields shown.

But which expression is the result? The pattern should be:

Min ( Max ( 0 ; result ) ; upperLimit )