Edit August 14: build is out now! See here.
Edit August 26: release 2.7.2 is not out too! See here.
The existing 2.7.1 release of TerrainControl (downloadable on Spigotmc.org) should continue to work fine on the lastest Spigot release, but Spigot 1.8.8 offers some interesting new functions for terrain generators like TerrainControl.
It is now possible to use block data during the initial step of terrain generation. Vanilla Minecraft 1.7 and up uses this a lot, but now it is also possible for custom terrain generators to use this. Previously, we had to use slow and ugly hacks to generate mesas and Mega Spruce biomes.
I hope to update TerrainControl in the following days to allow block data for settings like GroundBlock, SurfaceBlock StoneBlock, WaterBlock and IceBlock. SurfaceAndGroundControl will hopefully be faster and less buggy.