Good News! You solution works for both problems 1 & 2
For those with similar problems, follow Rui’s guide with a little twist as below;
– Create a draft page using the page builder
– In the page builder, switch to visual/text
– Paste your HTML code (ensure you add your open and close code tag in the beginning and end of your code in text mode)
– Switch back to classic builder. This should turn your HTML to shortcodes
– Copy all shortcodes shown
– Paste in modal
Works for me, might work for you. Can’t guarantee as I’m an explorer like you are. 🙂