I couldn't use a "ref" in the last letter in a word.

i have configured Avro and Windows correctly.

I think the problem is inbuilt.

You can not write the word "Somporko" (eng - Relation )

try to write this word...

Thank you Soumyabrata. This is a new bug you just detected. I've added it in the official Bug list and the fix will be released in the next version. Thank you again for your contribution in Avro Keyboard development.

But, It works on my pc ,

With Phonetic - "somporrko" সম্পর্ক
With UniBijoy - "nmgrjA" সম্পর্ক

But, in MSWord [below 2003] there is a bug, it shows ref in wrong position... You must update ur usp10.dll for Office to get rid of this...

Well, this is not a direct bug. But related with backspace function. Updating the backspace function in Avro Keyboard will solve this problem.