The 39-year-old has been a regular participant in hunter chases in recent years aboard horses he owns, most notably steering the high-class Mendip Express to third place in the Fox Hunters' Chase over the Grand National fences at Aintree in 2016.
The Philip Hobbs-trained Ballotin, formerly a smart performer in France, has also been bought to go down the hunter chase route, but could make up into a useful handicapper first judged on his winning British debut in West Yorkshire.
The 13-2 chance was strongly pressed by Monbeg River after the final fence, but dug deep to prevail by a neck.
"It's a great thrill to ride against professionals and it's massive for me to win a race like this," said Maxwell.
"It's the most fun you could have with your clothes on!"
Of Ballotin, he added: "He's a very good jumper - he has to be with me on his back!
"I bought him to go hunter chasing but he can't do that this season because he's won a bit too much prize-money in France.
"He'll go down the handicap route and could maybe end up in the Kim Muir at Cheltenham."
John Mackie's 5-2 joint-favourite Barton Knoll made it third-time lucky over obstacles in the Watch Racing UK In Stunning HD Novices' Hurdle, with Adrian Heskin doing the steering, on a day when the track officially opened its new £3.5million grandstand.
"He's over 17 hands and whatever he does over hurdles he'll be a better chaser," said Mackie.
"We'll see how things go, but I don't think he'll be jumping any fences on the racecourse until after Christmas."
The Jedd O'Keeffe-trained American Craftsman (16-1) made a successful start to his jumping career in the Globe-Trotting Joe Browns Juvenile Hurdle under Joe Colliver.
O'Keeffe said: "The first time he schooled him he jumped brilliantly, but I thought he might just lack experience today.
"He isn't the biggest horse so it won't be easy for him to carry a penalty, but he will improve."
Rank outsider Popelys Gull survived a final-fence blunder to cause a 28-1 upset in the Visit The All New racinguk.com Novices' Chase in the hands of Kielan Woods.
Winning trainer Pam Sly said: "He's been second a few times over hurdles. Kielan actually came and schooled him on Sunday. It was thick fog so I couldn't see a thing, but he told me he was very good."
Two Grand National-winning jockeys, Richard Guest and Leighton Aspell, teamed up to land the bet365 Charlie Hall Meeting 3rd & 4th November Handicap Hurdle with 11-2 chance Lough Salt.
Champion jockey Richard Johnson landed the final two races through Jimmy Moffatt's Nicolas Chauvin (8-1) and the John Quinn-trained Master Of Irony (17-2).
PERFORMANCE OF THE DAY
Having run an encouraging race on his first start for Richard Guest when third on the Flat at Ripon last month, Lough Salt skipped clear of his rivals in the three-mile handicap hurdle in the style of a horse very much on the up.
RIDE OF THE DAY
Kielan Woods cut a confident figure for much of the novice chase aboard Popelys Gull, but his mount nearly threw away victory by blundering at the final obstacle. Woods kept his composure, however, and displayed considerable strength in the saddle to sit tight before galvanising the five-year-year-old to get him back up and secure victory.
QUOTE OF THE DAY
Amateur rider David Maxwell after winning the Bobby Renton aboard Ballotin: "It's the most fun you could have with your clothes on!"