Nlundulu spent two-and-a-half years with the Whites, initially joining on loan from Cheltenham in January 2023 before making the move permanent the following summer.
The forward spent last season on loan at Cambridge after slipping down the pecking order and was told in the summer that he could leave the Toughsheet Stadium.
He completed a move to Paisley in the final hours of the window and has been building up his sharpness over the past few months.
Nlundulu netted his first goal for the club during Saturday's 3-1 defeat at Dundee United, nodding home after an error by the goalkeeper.
The 26-year-old admitted that his "journey was over" at Wanderers and it was a no-brainer when a move North of the border became a possibility.
"The gaffer's been very good with me," he told Daily Record. "Obviously, right he's given me my chance.
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"It's taken a bit of time due to fitness and things like that. I've enjoyed it. It's started well. At Bolton, it was quite a difficult situation. My journey was over there.
"When St Mirren came in on deadline, I just wanted to do it as quick as possible. The gaffer called me and we got the house on fire. Then it was a no-brainer, so I came straight up here.
"You can tell straight away how he is. His enthusiasm, his energy, his personality - which I'm a bit like that as well. That's why I feel like we've got on so well."
The forward added: "I feel like this is a good league to get my name out there - and it's like a restart for me."
Ahead of Saturday's game, St Mirren assistant manager Brian Kerr backed Nlundulu to get back to his best in the Scottish top flight.
"Dan's just getting up to a stage with fitness and we know he's a wee bit behind with a lack of games. The more games Dan plays, the more everybody will see what he really has to offer," he told BBC Sport.
"We know we've got a really excellent player there who previously has been signed for a lot of money, who has been at Bolton and a top league down south and a top side.
"So we know we've got a player with real assets. We just want to get the best out of him and being on the pitch over the next few weeks, I'm sure we'll get the best out of Dan."