Testing your theory has confirmed that this is a loading issue.



I learned two things from the tests:

1. You are 100% correct that PlanetImprovement.xml isn't loading properly. Making the change directly in the game folder rather than the mod made things work instantly. Oddly enough the custom descriptions DID load from the modded PlanetImprovement.xml, so it's not like it's completely ignoring the file.

2. Custom Terraformations don't work - they never show up on planets. This is probably hard coded. Luckily this is not an issue for what I wanted to accomplish as I plan to remove Terraform Barren and replace it with an end-game tech called Planet Creation.



Nevertheless, this wont work in mod format as long as the loading issues persist.

Since this got my curiosity, I just tried your "cheaty quick" method out...



This is the result:





So I have no clue what went wrong. Are you sure all the modded files get loaded properly? Because I had some problems with that in the past but assumed they are fixed by now.

I directly edited /Public/Simulation/PlanetImprovement.xml for this lil test.



Edit: After rereading your post I'm pretty sure it's a loading issue because you said you can still see Barren-Transformation on Desert and Lava even if you remove it. There is no way the file you modified is the one that got used. Now when I think about it, I'm almost sure, that it was exactly this file I had problems with myself back then. Maybe we should create a bug-report about this exact issue: "PlanetImprovement.xml from mod's not getting loaded" or sth. like that.



Try the same with the original file (after making a backup) and I'm almost certain that it will work.