Generating SHA1 based on fields of XML request and including it in DataSource Loop

I believe I have already solved the first and third part of my questions.

For the first part I have found a code snippet, which was relevant for me and generated a sha1 hash. The snippet was located here: https://gist.github.com/pditommaso/cf724c1d2353342784f0

For the third part, I found I was able to change the 'Target Step' property of the DataSource Loop. Which solved my problem readily.

I still haven't found an answer yet to my second question, so if anyone would be able to answer it, I'd really appreciate it.

Thanks for being my rubber duckies.