You don't have to lose your old neighbourhood to run it in M&G. Store Edition sets the EP version to 0x1F or a whopping 14 (0x0E) EP/SPs higher than M&G in the neighbourhood's ID Number (IDNO). To run it in M&G you'll need to change that in SimPe using the Hex Editor to a value of 0x11. It's not very difficult since the value of 0x1F is likely to only exist once. Store Edition adds nothing to the game so you won't lose a thing running without it.
If you don't understand how or can't do it, then if you can extract just the (IDNO) and can get it to me I'll change it for you.