If you want the multi-start algorithm to save more solutions then you have to set, e.g.,
MulStart::NumberOfBestSolutions := 5;
before calling the MulStart::DoMultiStart procedure. The algorithm will then store the 5 best solutions in the so-called solution repository of the GMP. To send a solution from the solution repository to the model identifiers you have to use the procedure GMP::Solution::SendToModel. See the attached example.