Saturday’s initial attempt to run the Supersport race was halted by a red flag incident in which the rider involved is understood not to have been seriously injured.
The restart was then delayed for a lengthy period in excess of an hour because of an oil spillage on the track, culminating in the race distance being reduced from seven laps to five.
Browne ran out a comfortable victor on his BPE by Russell Racing Yamaha, building up a healthy lead throughout and enjoying a six-second cushion over race one winner Paul Jordan at the finish, with Cooper a further half a second adrift in third.
Cooper set the fastest lap of the race, which was held in wet conditions, on his final circuit at 96.580mph.
Derek McGee, Conor Cummins and Shaun Buckle made up the top six, while Dominic Herbertson slipped off unhurt at Church Bends.
Browne followed that up with an emphatic success in the Open race on board his Honda Fireblade.
On still damp but slightly drying roads, the Cork man pulled clear of his challengers in the seven-lapper, winning by a margin of 16.3 seconds from runner-up Cummins, with Herbertson 3.5 seconds further back in the final rostrum position.
Jordan, McGee and David Datzer were next across the line, with Browne recording the best lap at 98.131.
Supertwin race two turned into a thrilling three-way battle at the front between Browne, Cooper and Jordan, with four-time British champion Cooper emerging the victor.
The Nottingham rider managed to pull away a little from the pursuing duo in the latter stages and had one second to spare over Paton-mounted Browne by the end of the race, with Jordan third on his Jackson Racing Aprilia, a mere 0.7 seconds behind the rider in front of him, with Herbertson fourth.
Browne dominated the ‘Race of Legends’, held over six laps after the first running had been halted after Marcus Simpson slid off unhurt.
The Irish rider won by half a second from Jordan, with Phil Crowe third, then Cummins, Herbertson and Michael Sweeney rounding out the leading six.
James Doy won the Lightweight race after leader Cooper came off unhurt at Church Bends, with Chris Meyer taking the honours in the Moto3 class.
Manxman Simpson edged out Phil Crowe to win the Classic Superbike.
