According to
res/raw/bn_avro.xml [inside apk]
the ":" character should show "ঃ" but it's not showing it. It only shows ":" character.
To verify I've tried the "^" symbol for "ঁ" character (which I also found in the same xml) & it worked.
Would be great if you could fix this. I can provide further information & vice versa if required.
Thank you for your hard work.