Hi,
Finally got it to work. It was all issues with ibus. In kubuntu 15.10, I was not having ibus as the default input method (even though my input method preferences said ibus was default). Setting it as default again solved the issue. However, I cannot type in varnam-ml in firefox. I switched to arabic to test and the characters print in firefox. Another weird thing is that I could not get ibus to work in ubuntu 15.10 unity yet, though it comes with ibus as default input method. Seems like ibus's behaviour changes from one desktop environment to another.