By the edit view we can not see calculations.
We are entering all amounts trough commas and by edit view we can’t see calculations.
But when we save the document then we can see all correctly.
Is there some suggestions?
Your decimal separator seems to be a dot, not comma. So try using a dot.
Decimal separator is decided by your regional settings under Preferences tab.
I have cheked it, but it shows for decimal comma (,) and for thousands space ( ).
Actually the settings are in this way correctly. 
When I try the same settings, I’m not able to reproduce this issue.
To be honest, I’m quite surprised your printed invoice shows decimal separator as dot even though your Preferences tab shows your decimal separator is comma. Don’t really understand how it can be possible.
What if you change Date and number format to something else… do you still experience the same issue?
So I tried some different settings. With latvian, lithuanian and german settings and they are working correctly.
Latvian date and currency settings have to be actually the same as estonian settings. Perhaps you can chek or give me some advice what I need to correct 
At the moment i will let it by the latvian settings, but …
Can you also try to see if you have this issue on some other computer?
Hello again
So I made different tests:
Win Server 2003 64 bit - same issue
Win Server 2012 64 bit - same issue
Win 10 64 bit (2 different PC-s) - same issue
Everywhere is Win in English, but regional settings are Estonian (thousand separator is space and decimal separator is comma).
With kind regards
Gunnar
This issue has been fixed in the latest version (15.2.50)