a far guess that the kcvinu problem is that his system needs to enable the support to east asian languages, in the case of windows xp it is in control panel like this: and it needs the windows xp CD, havn't tested it in win7 or more.
Click image for larger version. 

Name:	cPanel.JPG 
Views:	34 
Size:	68.4 KB 
ID:	9723

the Malayalam is displayed correctly on my english system with east language support using thinbasic scintilla editor, but the font size is very very small look the picture:
Click image for larger version. 

Name:	unicode.PNG 
Views:	20 
Size:	1.6 KB 
ID:	9724