The four sliders in the ENV section control the following parameters: attack (A), decay (D), sustain (S) and release (R). The envelope can be used to modulate the VCA amplitude and the VCF cutoff filter.
The LFO (low frequency oscillator) is a singled delayed triangle modulator. It has a frequency range from 0.1 to 30 Hz. The LFO has 3 destinations: DCO pitch, VCF cutoff and DCO pulse width.
The RATE slider controls the speed of the LFO.
The DELAY TIME slider controls the time required for the LFO modulation to start.