Randy Salvatore’s ambitious push to add about 1,000 downtown Hartford apartments has run into a string of supply chain woes, but the Stamford-based developer said he is still on track to begin leasing apartments in late spring. Salvatore’s company — RMS Cos. — has an agreement with the city to develop several vacant parcels around Dunkin’ Donuts Park, with a target of 1,000 apartments. Salvatore said his contractors faced delays in cabinetry, electrical supplies, roofing insulation, interior doors, appliances and more. Even so, they’ve been rolling with the supply-chain punches, shifting tasks as materials become available to keep the project’s first phase within a few weeks of its original schedule and within its $50 million budget, he said. Phase two will be split into multiple parts, with construction of a garage and 237-unit apartment building beginning in summer and lasting about 18 months at an estimated $60 million cost, Salvatore said. A second building containing the remaining units would be built at some later point, Salvatore said.