Evolve the number and slightly increase the effort put into the project Follow iene2.5 without decreasing effort (Evolve the number and increase the effort, but make the project look and feel like OS/2 Warp 4. You also need to follow IENE2.5 as close as you can without decreasing the effort.) Don't un-abbreviate this IENE outside of the title because Operating System/2 Warp 4 is more commonly known as OS/2 Warp 4. Note added by @OctoNEs: The current section of this IENE doesn't really match where IENE2.5 is at right now. Therefore, until 40, add in OS/2 Warp 4 features.
