Please note that right mouse click events are not supported in the version of the OpenLayers API which TWebOSMaps is based on. As such there are currently no plans to add right mouse click events in TMS VCL WebOSMaps.
Is this functionality available in FNC Maps?
Unfortunately not. However as TMS FNC Maps is based on a newer architecture and the OpenLayers functionality is based on a newer version of the API we'll investigate if right click events can be supported in a future version.
Alternatively right click events are available in TMS VCL WebGMaps because these are provided by the Google Maps API.