Android Annotations: Annotated class Xyz_ not finding it's original ("cannot find symbol class Xyz")

I use the latest Android Annotations 2.6 and IntelliJ IDEA. Sometimes I always keep having problem with the annotations / classpath / compilation order. Seems to occur irregularly. I had the project compile earlier today, then changed a res/layout-xml file later on, then I try to build the project and get an error.

But there are no syntax errors or anything in the xml nor java source files.

Problem is that the annotated class doesn't find it's original class, getting

cannot find symbol class Intro

error.

My project structure:

/src/
    /app/activity/Intro
    ...
/gen-annotation-processed/
    /app/activity/Intro_
    ...
/gen
    ...

My IDEA annotation preferences:

Processor path:

/path/to/project/ext-libs/androidannotations-2.6.jar

Processor FQ Name:

com.googlecode.androidannotations.AndroidAnnotationProcessor

Source folders in the project's Android IDEA module:

gen
gen-annotation-processed
src

Error login in IDEA when building the project (via IDEA, no ant or maven):

(Class "Intro" exists in the src folder and has no errors in it.)

Update: I have it working now, although not sure what/where I changed something after playing around with settings back and forth. It might actually just be an issue with IDEA and not actually android-annotations related, not sure yet.

What usually seems to work is: do a Rebuild (might throw compile errors, ignore). Then do a Build (not a complete rebuild). For some reasons, the multiple compilation runs don't work properly when doing a rebuild, need to do the rebuild+build combination.