To troubleshoot the problem of the site taking a long time to load, the system administrator should use Salesforce Community Page Optimizer. This is a tool that analyzes the performance of an Experience Cloud site and provides recommendations for improving the page load time. The tool checks for issues such as component density, image size, caching settings, and network latency.

To set up Lead Sharing or Lead Distribution for partners, two steps are to enable "Allow External Lead Sharing" in Digital Experience settings and create Assignment Rules for Lead Distribution. Enabling "Allow External Lead Sharing" allows partners to access leads that are shared with them through sharing rules or manual sharing. Creating Assignment Rules for Lead Distribution allows leads to be automatically assigned to queues or users based on criteria that you define.

Branding sets allow you to customize the look and feel of your Experience Cloud site by applying different colors, fonts, images, and logos. You can create multiple branding sets for different audiences and assign them using audience targeting. For example, you can create a special branding set for your Platinum customers and apply it only to them.