Initially I was unable to install on a live site even though I had a receipt for a licensed copy. Requested an explanation and their support staff responded quickly and professionally. Turned out to be a misuncerstanding on how to fill-in license form. My mistake. Module appears to be fine; good support.
Fails DNN 5.5.1 upgrade
Works very well -- easy to set up and use. Developer is very responsive to suggestions for new features and has several planned that will enhance this module's utility even more