NEW YORK (Reuters) -Kevin Spacey took the witness stand on Monday and denied claims made in a civil lawsuit by actor Anthony Rapp, who says the Oscar-winning star made an unwanted sexual advance in 1986 when Rapp was 14. Rapp, now 50, testified earlier this month that an intoxicated Spacey – then 26 and acting on Broadway – climbed on top of him at a party at his Manhattan apartment. Rapp, at the start of his own Broadway career at the time, said he was able to “swerve my way out” but that the experience scarred him. Spacey’s attorney asked him on Monday about Rapp’s suggestion during the tria…