Lewis Hamilton finished second for Mercedes and retained the lead in the championship by a single point.
Verstappen, who passed the Briton with four laps to go only to have to hand back the lead for exceeding track limits, finished a mere 0.745 seconds behind after starting on pole position.
"I wanted that MSC," the 21-year-old Haas driver told reporters during pre-season testing in Bahrain ahead of his F1 race debut there on March 28.
The IMSAC hearing and subsequent ruling was a consequence of an incident in the eighth and final race of the TVS One Make Championship 2020 at the MMRT on December 20.
The governing FIA's report into the accident said the fuel tank inspection hatch on the left side of the chassis was dislodged and the engine fuel supply connection was torn from the fuel tank 'safety bladder'.
The launch, presented online by "Quantum of Solace" actress Gemma Arterton, played up the 108-year-old marque's connection to the fictional British secret agent as the Silverstone-based team started a new era.
Williams said the 22-year-old, whose success in the all-female series boosted her profile in 2019, would "continue to be fully immersed within the team both trackside and certain Grands Prix and at the factory".
Mercedes won 13 of the 17 races last season, and have taken both titles for the last seven years, while once-dominant McLaren have not won a race since 2012.
F1 is still considering a Saturday sprint format, according to new head Stefano Domenicali.
The 21-year-old said he would drive for the ART Formula Three team.