Really your right code must be...
if(iAnimation1 and key(_1))
I was just explaining the mistake
In the wiki I used something like that. 1 starts/stops one animation and 2 starts/stops the another one. So this is what I done:
//Do nothing until the key is released
if(iAnimation1!=null) //If the animation wasn't terminated...
fli_end(iAnimation1); //...stop only the simple animation...
iAnimation1=null; //...and reset the handle
The complete code is in http://wiki.bennugd.org/index.php?title=Fli_end
Please take a look, as I'm using the same example for 4 functions.