The difference between a mini and a main event VSN is just the number of challenges. With this mini, there are six challenges happening live on Friday night. It's a warm up to the main event in February where there are challenges Friday night and all day Saturday.
When a challenge is a sketch challenge, I think that a person should be able to look at your card and see the sketch that you worked from. I, personally, will not be calling the challenge police. I left off a stem for my flower, but I did have my ribbon, sentiment and flower in about the same places on the sketch.
I hope that helps!