Issue with setting up Panamanian withholding taxes

Summary

Issue with 'use in withholding tax calculation' check mark at transactional tax when defining two withholding taxes. One needs to include transactional tax in calculation and one should exclude.

Content

We are facing a challenge with the tax setup for Panama. We need to setup two different types of withholding taxes:

Type 1: Withholding tax that deducts 50% of sales tax amount

Type 2: Withholding tax that deducts certain percentage of invoice amount excluding sales tax amount

Assume for an invoice both withholding taxes are applicable, with below example:

Line amount:        100,00 USD

Sales tax amount:  21,00 USD

Invoice amount:   121.00 USD

Withholding calculation should be: