At first I downloaded Avro 5.5 on my Windows 10. It worked perfectly for a while. Then word kept freezing each time I tried to switch to Bangla. So, I tried to check the compatibility. And may be while doing so I did something wrong. Now the top bar won't show, and the f12 key just opens a Doc saving dialog box. I can't write in Bangla.
I uninstalled the 5.5 version and then installed 5.1.0 from app store. I did this twice. The problems remain the same. And while on starting the computer Avro is supposed to be launched automatically and the top bar to be there by default, it shows another box saying-