Win SPM should walk you through setup the first time you use it. If you are using a modem, my advice is slow everything down! Go into the comm port properties and set it to 2400 baud, or even 1200 if you have problems with 2400. You also have to change flow control to xon/xoff. It doesn't plug in with a modem; it requires the 'assisted transfer' method. You dial a number, someone answers, and they transfer you to the internal modem by transferring you to *10. If you use the assisted transfer, you will need the password; the default (used 99% of the time) is craftr4.
If the Magix and the PC are at the same location, I would recommend using a direct connection. The hardware is a little tricky to set up the first time, but once you get it working it is much faster. You need something called a 355A or 355AF (female) adapter; if you do a google search you will find people who sell them.
The 355 goes into a 25 pin to 9 pin reducer, which then plugs into the serial port on your PC. If your PC doesn't have one, you need to purchase a USB to serial adapter. I have done this multiple times for my customers, and it is always a surprise to see whether the set I have purchased works or not. The one I am using now (because it has all the pieces in one box and works) is made by Gearhead, and is labeled as a "USB to Serial DB9 calbe with a bonus serial DB9 to Serial DB25 adapter." It is model CA2000, although I think that was changed last time I ordered one. I order them from Frys Electronics on line for $20 I think. So...with that, plus the 355A/355AF adapter, you do the following: Data cable to the plug on the processor of the Magix that says admin. The other end of the data cable plugs into the 355, which connects to the 25 to 9 pin reducer, which goes into the serial to USB converter, which plugs into your laptop.
With this connection, make sure you again go into the properties of the USB port (once the driver is loaded it will show under LPT and comm port connections and slow it down and change flow control to xon/xoff.
Hope this helps...