Hey,
A lot of glyphs unavailable in Keyboard, in case of Arabic fonts, so user need to insert it to write a words inside test desktop font, as I suggest in the picture below:
You can only use characters (e.g. glyphs with a codepoint), but you can already type those, right?
Hello Erwin,
My Arabic keyboard covered only Arabic Presentation Form B, some fonts that I had made covered Arabic presentation form A (this used Arabic glyphs but for other languages like Urdu…etc) that’s will mean I couldn’t test it, because it’s character unavailable in my keyboard. I could test it after exporting font to windows, then used Microsoft word (by inserting symbols), but the suggestion is to make this issue from inside FontCreator.
I will add this request to the to-do list.
Nice, Thank you
Perhaps a drop down character selection grid like in the ‘Character Map’ program somewhere in the preview panel would be quite useful in a limited number of circumstances (for me at least) as an alternative to typing for more arcane languages like Georgian and Armenian because I only have a Latin keyboard. 
my 2¢