Here are described the settings and best practices to setup beautiful real-time shadows in Verge3D for Blender.

Global settings

Being computationally expensive, shadows are disabled by default. You can enable them under the Render tab in Verge3D Settings panel.

On the same panel Map Type allows you to select the shadow rendering algorithm – you can use this switch to trade between speed and smoothness. Shadow quality increases and performance decreses in the sequence of the options Basic, PCF, Soft PCF.
Map Side denotes which side of polygons is rendered during the shadow pass. Selection for this option should be considering when setting up Bias (see below).

Per-light settings

Shadows can be enabled/disabled for each individual light using Blender's native Shadow panel. Any other settings from this panel are not supported.

On the Verge3D Settings panel can be found some per-light settings. Size/FOV, Near and Far can be used to tweak the shadow volume (the less the better). Radius controls the blurriness ratio, Map Size – how big is the shadow texture (trading between speed and quality).
Bias can be positive or negative. What to choose depends on the above-mentioned Map Side setting. If Front Side is selected, the positive Bias should work well (and conversely, Back Side – negative). Tweak the Bias until you get rid of self-shadow artifacts and/or the peter-panning effect.