From a LMMS perspective it's simple.
LMMS comes with an older versions of the calf plugins.
Its not as easy as just adding the newer versions, because they are in a different format and LMMS tries to be backwards compatible.
So, that if you load a track made with an older version, it will sound the same in a newer version of LMMS.
If only I could hire a few coders, fix anything Carla related in LMMS. I think Carla in LMMS has the potential of fixing a lot of shortcomings of LMMS.
(Plugin related)
Carla supports about all. Last time I tried though, I could not automate any knobs of Amsynth in LMMS.
Falktx is on the LMMS dev team though, so all we need is patience. (and stay optimistic)