I assume you are talking about a version 3 MPP. There were earlier lower resolution units that were almost useless. A version 4 machine can load version 3 stuff. But, anything saved with the version 4 machine will not load into the older unit. If you have any problems, I can convert anything you need. You would be much better off with a version 4 unit.

Yesterday I bought another MPP for $150 plus $15 shipping. There are several on eBay but you need to be cautious about which one you buy. I saw one that was not fully functional.