Julief,
I don't have a blade by the name FD-UV. I think you are talking about the FD-UR. Most are now using the blue painters tape on top of the wood and glue the pattern on top of the tape. The tape has a chemical on the top, so you can un-roll the tape. It is some kind of silicone and it releases friction.
About sanding the back of the blade. If you are not very careful, you also might also hit the teeth. I never had to do this.
FD Mike