Candidates for RTD’s Board of Directors largely agreed during an election forum Thursday that the transit agency must focus on solving its workforce shortages — while at the same time figuring out ways to raise serious money to pay for the future aspirations it recently charted out. Much is at stake in those knotty challenges, from how quickly the Regional Transportation District can reverse some of its pandemic service cuts to how fully it can adapt to changing transit needs in coming decades. “We’ve got to figure it out, and it’s going to be a tough conversation,” Michael Guzman, said about the prospect of raising billions of dollars in funding called for by RTD’s Mobility Plan for the Future, which looks ahead to 2050.