I am not sure if I understand your question - I assume you ask what happens if you define the following steps:
Step No. Coeff.
1. 0
2. 0.5
3. 1
4. 0.5
5. 0
where you apply a load case with a force of 0.01 MN.
As loads are incremental in ATENA, this means that in the first step, no force is applied. In the 2nd, a force of 0.5 x 0.01 MN is added, resulting in 0.005 MN. In the 3rd, 1 x 0.01 MN is added -> 0.015 MN total at the end of step 3. In step 4, another 0.5 x 0.01 MN is added -> 0.02 MN total. The 5th step changes nothing, leaving there the 0.02 MN.
Please do not forget that if you use the Arc Length method, the load can be scaled in each step and therefore the step coefficients are not enough to tell the actual load any more (therefore, monitoring the load is critical with AL).