I have installed Activity Launcher 1.2 Script and imported it in my windows live messenger..when i want to launc a game i click on of the games on list but nothing happens..same problem with non-games applications..any idea??

The general problem with the Activity Launcher script is that it would need regular updates to reflect changes in the available games / activities.
The last update was done in late 2006 so I guess many activities don't work anymore and new activities aren't on the list, so the list would need some major updates.

Concerning your problem, does this happen only with certain activities/games? If yes, then it's the issue of the list not being up to date.

(original Activity Launcher thread: [release] Activity Launcher [Update: 1.2, Wow! Even More Games!  3 Sudoku Games! ))