Hello Benjamin,
The my portfolio tool is not designed to track live intraday performance. There are tools out there that can do that much better than we could so we thought, let’s stick to what we know (strat.developement) rather than build another one.
When you are viewing a portfolio in the portfolio library (or in any other page), you can go to the asterisk on the top right of the page and click it to “Set as my portfolio”. To combine strategies you need to use the portfolio builder.
You cannot combine multiple portfolios into one online. Here is a guide on how you could do it on your own using a spreadsheet:
https://logical-invest.com/create-portfolio-of-portfolios-portfolio-builder/