Using lua script example

Hi, can someone please tell me exactly how to use lua script in visionaire?
I'm a newbie and i just want to know what i need to do, so my script starts when i press start(F9).
Is there a special syntax, or do i have to say somewhere, that i want to use my script?
I would really appreciate any kind of support.
Edit: in scene -> actions -> at the beginning of the scene I'm already calling the script, but it isn't working.
Edit²: tried out random lua scripts, it's working. so i guess the problem is, that i'm trying to change a condition from a scene object in a wrong way.
If the condition is a variable, then i just should be able to change it in lua script with
conditionname == whatever
.. but it isnt working, could someone tell me how it is done correct?

Can you post some screenshots & the code you are trying to use please? as well as provide me with a clear understanding of what you are trying to achieve. Cheers.