QWERTY Phonetic Bangla Layout updated with new intelligence implimentation. So now when you press and "kar" following another "kar" or "space" - it will display the vowel itself, not the kar. For example check the following sequence:
a = আ (previously it display া ) and kha = খা khai = খাই (previously displayed খাি)

Now "=" also works as a joiner and "==" displays the "="

The new version is available from here, which is a part of Bangla Typing Scripts for Web Pages.