The one that seems to be recommended these days is MM7CHE.EXE. I've not used that one though; it wasn't around when I had to do this. The one I used was St0rmcat's MM7view. It's very powerful (or at least it was considered powerful then), but although it's not rocket science, it's less user-friendly than some. Then it's a question of find the precise filename of the savegame you want to edit, and applying the editor to it. IIRC, it was easy enough to do once you'd figured out how use the editor. You'll find both these editors at the link below.To patch the game, you first need to check that the problem is that you've got the v1.0 version. You do this as follows:
Load up Windows Explorer, find the mm7.exe file, and right-click on the filename. In the drop-down menu that appears, click on "Properties" (at the bottom). in the window that opens, left-click on the "Version" tab. In the panel labelled "Item Name" in the lower half of the window, left-click on "Product Version" and read off the version number in the right-hand panel.
If it reads "1.0", then you need to go to the link below and download the file mm710-11.exe, and run it, using it on your file mm7.exe. If it reads "1.1", then you have a different problem, and I'm afraid I don't know what it would be. You'll have to get back to us and ask for Bones to help you.
Good luck!