No, there is no such option. Only if you are a fee-paying participant, you may chose another place to stay, which does not reduce your registration fee. No problem at all. If you inform us in advance, the kitchen will prepare special vegetarian food. Your chances of getting accepted for a second time are relatively slim but not excluded.
Priority is given to new applicants.
If I sent an application last year as well. No, you don't need to call. As soon as your application is registered you will get a confirmation mail. You are supposed to receive notification mid June. Original documents will follow by post.