Spencer Bassett added a try for
Dunvant and Sweeney contributed another conversion and penalty to send Ponty home with the points.
But Cantoni had already completed his hat-trick then added a fourth try for
a 38-point lead before a belated rally.
Carter scored his second try for
Cinderford just before the break to leave the half-time score 27-20 to the visitors.
Eventually, wing Steve Barnard wriggled over for his first try for
Rhymney that Lee Williams converted but the Illtydians were left to cheer a valuable win.
Luke Gross replied with a try for
the Scarlets before Lewis' second and the boot of Ceri Sweeney proved enough as the home repelled a late Llanelli surge.
Coventry secured their bonus point with a fourth try on 23 minutes with a sparking try for
Martin Davies and a third conversion.
Wing Brynmor John replied with a try for
the Athletic and fly-half Nick Thomas landed a penalty.
Barry Muir converted an Oscar Wingham try to level matters on 28 minutes but Swindells converted Alan Dickens' try and in stoppage time Manchester scored another converted try for
a 14 point advantage.
Elliot Spencer scored a try for
Nottingham followed by a penalty by Southam.