Save a new file with macro

hi everyone i'm trying to make a macro that make a new part from zero, make some drawing and then, with the help of a userform for selecting a path and a name for the file, save it in the desired path. With the first two step i'm ok, but for the last step i have some problem. Online i found some solution but it all pass from the "save as" window and i don't want to let the user to choose the name of the file. the problem is that i'm trying to save a part wich has never been saved. someone cane help me?

SolidworksApi/macros