Changing princing schema

[gastn_jareo]

I'm programming a complex formula. It's deffined on VOFM - Formulas - Condition value. It's used on VA01 transaction to calculate sales orders tax perceptions.

Acording to some data on Z tables the percetion % changes, or turns cero, so every standard calculation may change inside the formula and I change XKOMV values for it.

And we have minimum values too, so may be some lines has cero but if you insert a new

I made the changes but a lot of strange things happens. I've saw that the internal table GKOMV left bad so I change some values on GKOMV to give it well... But it didn't work.

I think I'm changing bad something or I'm forgotting something, or I'm changing it out of proper time.

Are there any formula to do what I'm triying to do manually on formula script?

Any other sugestion?

I really don't know what to do now! And the calculate it's really complex, so it's not possible to do it only buy custommizing without ABAP programming.

Thanks in advance!

[gastn_jareo]

Nobody can help me?