i created an entity and in its properties I made it invisible and passable but on running the level my charecter always getting collided with the entity which should be passable....

The bug forum is for bug reports and not for beginner's problems. If you want to post a bug report, please read the introductory text of the bug forum first. The PASSABLE flag works, but if your script doesn't, the first thing you should do is trying to find the reason. Some advices:

http://manual.conitec.net/debugging.htm

If you can't find the problem yourself, you can ask for help on the Lite-C Programming or Starting forum.

Ah, this manual page is well done, very helpful for beginners.