the fields %TaxName% and %TaxValue% disappear

the fields %TaxName% and %TaxValue% disappear

First of all sorry for my english!
I'm trying to work with Zoho Invoice!

I have to solve 2 problems:

1 - I customized the invoice template but when I export it to PDF,  the fields  %TaxName% and %TaxValue%  disappearThe fields work correctly except when I export them to PDF.

2 - Is it possible to manage multiple expiration date in the same invoice?
for example total invoice € 1.200
expiration date : on 31/01 € 600 and on 31/03 € 600.
How have I to do?

Thanks in advanced for your answer.
You find here attached the txt file of custom template.

Best Regard.

Andrea