Why RichTextBox with ProggyClean font changes to Arial?

Question

Hi,

I try to use ProggyClean font in RichTextBox.

Setting Font property (design time) and filling with text (runtime) works fine.

When I start writing the text, font changes to default Arial.

I have installed three different languages in the system:

• EN English (American)
• FR French (France)
• PL Polish

What I have observed:

• ProggyClean haa only one Script (Charset? Codepage?) defined and it is Western,
• when I use input language EN or FR (which operates in Western Script) there is no problem,
• written text in the control automatically changes to Arial when I use PL as input language (which operates in Central European Script).

And the question:
Is it possible in RichTextBox to use Western-Charset font in non-Western-Input-Language mode?

Due to floating point number reading issues I have line in the code:

Application.CurrentCulture = new System.Globalization.CultureInfo("en-US");

Additionally I tried setting the following:

InputLanguage.CurrentInputLanguage = InputLanguage.FromCulture(new System.Globalization.CultureInfo("en-US"));

but it is not a solution, I don't want to change someones AZERTY to QWERTY keyboard layout.