Buttons in external swfs

Hi,
First post here, so be gentle.
I am having a problem getting buttons in my external .swf movies to load their appropriate content.
In my main timeline of my root movie i have 4 buttons on the stage. One of these buttons loads in a new external swf onto the stage. To do this I use this actionscript to call the movie:

_root.buttonmc.button1.onRelease=function() {
if(nextMovie!=“content4.swf”){
nextMovie=“content4.swf”;
_level1.gotoAndPlay(“outro”);
}
}
This works perfect and loads in the content 4 movie. In the content movie I have another ten or so buttons which will load at the top of the page. when one of these buttons is clicked i want another movie to load directly underneath all these buttons. i want to keep all these buttons on the stage as these movies are illustrations i have done and i want each illustration to load and the user be able to navigate through them with buttons above them. i have created each illustration as a separate swf file as i want to do nice transitions between them. the actionscript that i use to control these buttons is basically the same as the script from my main menu:

_parent.hellotheremc.madbutton.onRelease=function() {
if(nextMovie!=“content150.swf”){
nextMovie=“content150.swf”;
_level1.gotoAndPlay(“outro”);
}
}

The content 4 movie loads in and the buttons appear but none of these buttons will work. any ideas what i am doing wrong. I think it may have something to do with paths but I can’t figure it out.
Thanked in advance