Well I'll give a look
The reason I'm doing this in python is that because the game will be 99% editable, I want to let users mod what they want using python (editing txt python file then they are executed by construct)
Edit : another reason is that with python I can have temp variables and with events I'd have to create useless global variables...
Edit 2 : String addition is not the reason, if I replace all my script by anything in python (example : print "hello") it shows me the error message too...