try to go through the tutorials at
MTS2 - they tell you a lot about meshing, SimPe, cloning meshes (which might be the problem you have), and a lot more.
And I suggest you try to actually find the files you want to work with before you start changing them. Keep things named and in folders, so you can find them when you need them.
We've not seen your desktop, or the file system on your computer, so we can't tell you where you put the file.