I started too but converting health into happiness was problematic.
I also ran into issues trying to lift the graphics and place them into Civ 5 in a 1:1 fashion.
I considered alternatives such as simply ignoring adding health into happiness but not being able to import the graphics was too much since that is important to the 'feel' of beyond earth and I am no artist so drawing new assets just wasn't going to happen.
There was also the issue of importing the science web. It's easy enough to slap it onto the end of the science tree but in what order and fashion? Games of Civ are supposed to be over before you start researching 'future tech' so do I replace the tree completely or intertwine the two?
If I lifted BE direct into Civ5 then you may as well just buy BE at that point and that would also pronouce my inability to make health = happiness.
The reason I struggled with that by the way is because it is not a tile yield. I tried copying the xml format for natural wonders but that didn't work out and even if it did, may have broken the game since if every biowell became a natural wonder they may also become unpassable (all land NW in civ5 are tiles you must navigate around, not through)
It wasn't enough to just transplant Civ:be into Civ5, it needed to fit in a natural way and it also needed to end too. Players might play for longer to enjoy the civ:be features but it would only be once or twice because the science tree would be too rediculously long.
There is also Affinity to transplant but honestly I was going to leave that out. Looking at LUA for making that fit in correctly and I am a complete novice with that side of things. I suspect it would have helped with happiness yields too.
Due to the mod friendly nature of Civ games, if you can import the graphics then transferring the XML data and making it 'work' in Civ5 is a breeze! Which I was able to do. Using existing Civ5 graphical assets just doesn't look or feel right.
BE is essentially a mod of Civ V, that took quite a bit of time and money to create. Why would anyone want to duplicate this effort?
While I would argue Civ:be "is just a mod" having looked under the hood, I would agree with the statement it took a lot of time and effort and was the work of a
team. Asking a lone modder to recreate all or even a fraction of that, is asking a lot! There is a reason we didn't see an influx of 'civ4' mods, when civ5 first came out (and was bad).