Controls

The basic controls of ReaComp are:

Threshold - Lower the threhsold to catch peaks, or delve deep into the innards of an audio signal.
Pre-comp - Look-ahead compression.
Attack - From 0ms to 500ms (5 seconds)
Release - From 0ms to 5000ms (50 seconds)
Use Auto release - Automatic release
Ratio - From 1:1 to 100:1 (inf)
Knee Size - From 0db to 24db - This will tell the compressor to either start compressing as soon as a signal goes over the threshold (0db) or start compressing after it goes over the threshold by a pre-determined amount (i.e. 1db to 24db).
Detector Input - This is used as a key input for sidechain applications
Low Pass/High Pass - Choose to NOT affect a certain range of the signal being compressed - very useful to avoid inadvertent bass compression
RMS size - This is an RMS detection function - generally, setting this value low gives more compression, and less compression when set higher.

Tutorials

Here are some videos on how to use ReaComp step-by-step:

You can find some ReaComp presets in this forum thread.