Hello, thank you for your patience! To answer your questions:
1) The MICCAI workshop will be held in person at the 2025 conference. The MICCAI organizers have not yet given more information on what the exact setup looks like, so we also do not yet know if the workshop will be livestreamed too.
2) For the development phase, while possible, you are not required to submit detailed information about your model. However, when submitting to the test phase, we require the submission of a pdf file with information about the submission (model, data it was trained on, etc.). If you wish to make it citable, you are free to write this in article format and put it on Arxiv, but you are not required to do so.
3) We are not yet able to disclose the exact monetary prize for top-performing teams, but we can say there will be both prizes for top-performing teams at the end of the challenge, as well as early-bird prizes for the highest performance before the 30th of June. You can find more information about this on this forum post.
Hopefully this helps!