Even if the self-hosted version does include the full source code, we would strongly advise you against tweaking the core files. Doing so may result in:

• Upgrade problems. Every upgrade resets activeCollab files. This means that you will have to reapply and test your changes every time you update the system.
• Avoiding upgrades. We iterate fast and release new versions frequently. By choosing not to update because of potential issues, you may end up using old builds, instead of enjoying new features, enhancements and stability improvements.
• Losing Support service. Changing the core files usually means that our technical support team will not be able to help you debug activeCollab or resolve potential problems.

Please note that we do not offer any assistance with core file modification. The best way to maintain a stable and reliable platform is to use stock activeCollab. Instead of modifying the core files directly, extensions should be implemented by:

• Creating a custom module
• Integrating external applications via the activeCollab API

By extending your platform this way, you will be able to upgrade activeCollab, while retaining the modifications made to the system.