I tend to wonder wheter a spline fit using spaps or spaps2 would be the way to go. You could then use fndir and fnzeros to get the locations of all the max and mins. You could fit the mins using spmak to get your "baseline".
If nothing else, this would at least give you an estimate of the number and locations of the peaks, which you could then feed to lsqcurvefit to build whatever model you wish. I think a sum of Gaussians would be a difficult fit, though. You couldn't assume that 14 Gaussians would be a good fit just because you see 14 peaks, for example.