1. Personally I mostly use DynaVerb for Swells (Dynamic Reversal) and for doing stuff like making a room sound bigger the harder you play.
2. There are two classic compressor topologies. A Feedforward compressor gets level directly off the input signal and uses that to control the Automatic Gain. A Feedback compressor actually uses the level after the Automatic Gain to control the Automatic Gain. So, we took it a step further on the contour knob by allowing you to mix between these two signals. Does that make sense? It can be a sublte effect in Omnipresor only mode. It's less subtle as sidechain mixer in the Reverb Mode.