Please check whether you followed below steps or not:
1. Login into your native-language (Tamil here) first.
2. Check for necessary package installations.
[ankit@host59 ~]$ rpm -q scim scim-m17n m17n-lib m17n-db m17n-db-tamil
3. If any of the above is missing do "yum -y install <package_name>"
5. Right-Click on the Keyboard icon on the top panel => Scim setup =>
Front End => Global Setup => Trigger => Control+Space => Press "Apply" -> "OK"
IMEngine => Global Setup => Enable the languages & layouts you want.
6. scim-restart OR Logout -> Login again in your native lang (Tamil here)
7. Run your prefered application (OOwriter here)
8. Press Ctrl+Space & you should be able to start typing in your native langugaes (Tamil here).
After following steps 1-6, you don't need to repeat 2-6 later on. You need to do 1,7 & 8 only.
Btw, the screenshot you attached: http://forums.fedoraforum.org/attach...chmentid=12364
is for xkb input method. You don't need to play with it, while working with scim. Please reset it to defaults.
Let me know, if still it's not working.