Two troubled downtown condo projects -- Sabine & Star Riverside -- have run into financial problems and been posted for foreclosure.The failure of these projects is a combination of market conditions and their own troubled history. The Sabine is a troubled 10-story office building conversion project at Sabine and West Fifth streets that was completed in 2007. With 44 of the 80 units unsold and litigation between residents and the developer over sued . . .