Application descriptor file won't save. Air/ActionScript

I'm creating a mobile app with the actionScript/AIR 23 and when I change my application descriptor files it works only once. Both only save (Main-android-descriptor.xml and Main-ios-descriptor.xml) the first time but when I debug the application a second time I have to make the changes again (and for subsequent debugging). I specifically changed the following setting in the application descriptor file:

from:

!--<renderMode></renderMode>-->

to:

<renderMode>direct</renderMode>

What is happening here?

I have other applications that work in this set up but I'm not sure what's happening here.