Sometime, situation got arise to me that i have to type nepali unicode . For enabling this capability in Ubuntu,  i  install the language support for Nepali inside system settings. After that, i configure nepali keyboard from text entry  again inside system settings. Now, i can switch to nepali keyboard and type in nepali unicode as usual. After that, i download and install the nepali unicode font by double clicking or right clicking the font. I usually use kalimati.ttf font for typing nepali unicode.

Cheers!