It is 8 separate polysynths each triggerable by one or more of the notes that are played on the keyboard i.e if you have synth 1 only responding to note 1 it will be monophonic, if you select more notes it will be duo, trio polyphonic etc. As well as responding to notes played each synth has an step sequencer so you can have the first 2 notes played triggering two different sequences and 3rd and subsequent notes playing a lead-line.
Therefore the area top right is key to its behavior.
The step sequencers, as well as triggering notes can be used to affect filter cutoff or sync sweep or FM on each synth.
Also unique to Kaskade (I think) is a filter which can be varied continuously between Lo band and Hi pass.
Please give feedback to the author here.
More info: Kaskade Public Beta free VSTi