i've been trying to dig into this myself, and i enabled those two command parameters to test something. right now, they're somewhat useless...
the PK_Effects only work on UI2, and are OpenGL based. The code for them is being compiled into Orbiter, but I am having difficulty figuring out what even makes them trigger. The relevant tables are Effect and EffectType, and range from some fades to basic bezier animation.
We also have the ability to play back MNG based files for designobjs in ui1. This should only be used for nice square areas, because each frame is pre-rendered. However, I also do not know how to properly implement this, as experimental changes here in designer are not working.