CalcyPy options

[Niefer]

I have set the following CalcyPy options:
Decimal point and group separator = System default
Decimal output Precision = 3
Show group separator in result = Checked

My Windows Control Panel \ Region \ Additional settings... \ Numbers settings are:
Decimal symbol = . (dot)
No. of digits after decimal = 3
Digit grouping symbol = (space)
List separator = , (comma)
And it shows the example - 123 456 789.000

Now for what CalcyPy does:

• if there is an integer, the group separator , (comma) is displayed instead of (space),
• if there is a decimal number, it doesn't show the group separator at all.

Is this a bug or did I just set the wrong parameters?