By GINIA BELLAFANTE

Kim Basinger's current financial troubles seem about as heart-wrenching as those of Indecent Proposal's poor beach-house-deprived Demi Moore. Nevertheless, according to Basinger's attorney, HOWARD WEITZMAN, the actress was forced to file for bankruptcy, because she could not post the $13 million bond that would have allowed her to process an appeal against Main Line Pictures, the production company to which she must pay $7.4 million for backing out of the psycho romance Boxing Helena. "How someone who makes $3 million a movie can go bankrupt is beyond me," says angry Main Line president Carl Mazzocone, who's determined to extract his cash. He'll need more than determination. Basinger insists she's worth a paltry $5 million.