Hello Daphne,
There may be a few issues at hand with the designs.
1. Are you doing three (3) consecutive designs that you have programmed into your machine - designs that will continue running? Check to be sure fabric is in hoop securely and screws tightened just enough so as not to loosen fabric while embroidering.
2. Are you doing three (3) designs that you must stop after each one and move the fabric around in the hoop?
3. When you say "corrupt"....is the design puckering? Fabric may not be in hoop tightly enough. is the design being embroidered on top on itself?
4. Are you doing the placemat in the hoop? Maybe working outside the hoop might be beneficial.
5. During the first run of design, has your hoop hit anything accidently to put the hoop a-skew? I have done that myself when my machine hits the wall and I did not realize it until the design was all fu-barred.
Have you tried again since you received all the replies?
Joan/NJ