Quick checks
If a page is slow, reload it, then try another page such as the films list. Most slow loads come from the connection, and a reload usually sorts them out.
Another device
Opening HDPro on a phone with mobile data shows quickly whether the issue is the home network or the site.
Your list is safe
My List lives in your browser, so it stays in place through any reload. Export it from the My List page for a backup.
Watching
Films and series play on the official services, so a title you have started keeps playing in the service's own app.