The "Top-to-Down" idea will mean to create replacement for:
- Workplace Shell
- System Object Model (SOM)
- Presentation Manager (PM)
- Workplace Shell - XWorkplace - GNU GPL V2
- System Object Model (SOM) - SOMFree - GNU GPL and LGPL V3
- Presentation Manager (PM) - FreePM - BSD License
The idea of starting "Top-to-Down" is to be able to put more open source replacements over a working OS/2 Warp 4.52 or eComStation 2.1. Even that both products are still commercial, it will be a good start to run this components on the top of this OSes.