Tracks uploaded to someone else's projects are added as Idea Tracks. This is a special designation that indicates that the file is not yet officially part of the collaboration. The owner of the collaboration will be notified and will do one of three things:
Option 3 is greatly discouraged, and there are features built into Kompoz to try to prevent that. Most likely, the owner will accept or archive the idea track, and add a comment to provide feedback.
If your idea track is accepted, then you will be added as a participant (collaborator) within the project automatically. The project will appear in your Collaborations Joined list within your workspace.
You can keep track of all pending ideas from your workspace page.