Ignacio (or Alfredo?), UUID field needs to be included in the screen for MIRO and you can't put a RAW type field on the screen. This note is a consulting solution, not supported by SAP, please make sure to read everything carefully.
Regarding other question, your choices are either to make a modification or implement the whole bunch of notes. Which one is "best" everyone would have to decide for themselves. I chose a modification because it's simpler, has less impact and in the next upgrade we'll just remove it.