FYI, the Topal Bay Walkabout is very resource intensive - be prepared for reduced FPS. And in my opinion, not very fitting to the nearby geography and flora. There are plants from SI that can be found in the walkabout area, and I am just not happy with that.
I too have some issues with the mod, however, on the plus side, the author dose attempt to justify the SI plants via diary/journal entries (I'm an easy sell when it comes to plausible lore bending), and he states his intention to return for an update, after completing a current project. Says he wants to lower the FPS hit and finish a couple of sealed off areas in the walkabout dungeon. I've got my fingers crossed.
This mod along with maybe a dozen others, fall into my “diamonds-in-the-rough” category. A mod that really grabs my attention for some reason (innovative, unusual, unique aspects, creative use of standard resources, something) that sets it apart from the typical. It saddens me that they are often never given the final polishing I think they deserve. And although I know I have no right to expect more of any mod maker, I never-the-less hold out hope those diamonds-in-the-rough may someday shed those rough edges.