Just so, the segment editor and the entity thumbnail maker are both internal tools that look visually poor compared to the FPSC interface, and few user safeguards. Rather than invest time making these releasable, we put extra energy into the main EA components. For those more than eager to create segments and entities, you can skip the use of these editors and start looking at the FPS and FPE text files themselves. I could release pages of information how they work, and I hope when a few of your read through them the explanation (in the main) will be unnecessary. I can answer specific questions in that case to help along public knowledge of the subject. Generally however, I do not expect wide customisation at the sub-segment and sub-entity level until I release some high-level interfaces to make the process painless.
We may decide to release the segment editor and entity thumbnail maker as a seperate special release for the hard-core users who do not mind the lack of bells and whistles and happy to live with the odd lost segment, disappearing meshes, and odd behaviour of these internal tools. If I get a few requests for same, I will bounce the implications of releasing these internal tools around the team, then decide from there.
"We are the knights who say...eki eki eki fatang loopzoing, zanziga....ni"