I cant say how all work...but my re-writable for the husqvarna rose needs the card reader/writer box and the software to go with it...one inserts the card into the reader/writer box...opens the Reader/writer Pro NT software and import files onto it....then it overwrites everything on the card. Does that help much?

I have a Bernina and use the 200 Personal Design card. The only way a file is over-written on my card is if it has the same file name as a file already on the card. It basically works just like any other memory card. Like the cards for your camera.

I have a Brother machine and PE Design. The software overwrites anything on the card when you write to it, so you can't "add" to it.

I have a Platinum Plus D-card reader writer. I used to have the Rose. With both cards you can add a design. When you READ the card on your computer and then WRITE the card, the computer will ask if it's ok to delete the current designs. That will not take the designs off the card, you have to do that manually by 1st reading the card, and then selecting the design and pressing the delete key.

I cannot get my reader writer box to work - it used to be just fine with Windows 95/98 now I have Window XP and all I get is error re "reader writer no found" reading I found something about needing updated drivers, of course I am not very good with computers can anyone shed light on this, I have tried to located husgvarna dealer in our are but have none; Thanks - just stuck!