Hi Faival,

I assume that you are exporting a Mac OSX application because you are on a mac. Which jar file did you try to run from the command line? The jar file inside the exported .app bundle?

Anyway, it looks like it cannot find the PApplet class (inside core.jar ?) when you run the jar from the command line. This might be because it is not in the classpath. (use the -classpath option on the command line for the referenced jar files, and the -Djava.library.path option to point to the referenced native libraries).

But it's easier not to run it from the command line. Maybe your exported mac app does not work because it cannot find the native libraries. You can check for error messages in the console.

I do not use EclipseP5exporter, but maybe it works if you put  -Djava.library.path=[path to your native files] in eclipse in run --> run configurations --> your main class --> arguments tab --> vm arguments.

You can also try to put your native files inside the exported app (right click and choose 'show package contents), in the contents --> recourses --> java folder (I think that folder is automatically added to java.library.path).    

In stead of EclipseP5exporter, I use in Eclipse in Mac OSX:

file --> export --> other --> Max OSX application bundle

This makes an application bundle (app). If I add the native files to the build path of my eclipse project, it adds them to the classpath of the exported app, which makes no sense, but it also exports them automatically to the contents-->java-->recourses folder. That made it work for me.

If you do not want to have your native files inside the application bundle you can also set java.library.path in the info.plist file in the exported app, but you have to google for that.

Good luck