Amortization and FX Valuation in one step

Hi Experts,

I have customized a product with product category 550.

I need to make the valuation of amortization and currency in one step.

I find that it is only possible in NPV valuation (Define One-Step Price Valuation Procedure) but not in amortization procedure.

is there any way to make that? 

Thanks in advance,

Sebastian M