By default, Simple Calendar will use WordPress own setting for the start of the week. This is set inside General Settings page from the Settings menu in admin dashboard.
However, you also can adjust the start of the week for individual calendars using the corresponding setting inside the Advanced tab in the calendar settings panel.
Calendars are post types, a WordPress content type like blog posts or pages. By default WordPress adds all your posts, regardless of their type, to your feeds.
If you want to tweak your RSS feeds you need to use WordPress functions and hooks. But you can also use a third party plugin, such as the popular Yoast SEO.
Google Calendar app automatically detects the location of the current user and adjusts the displayed event time and date according to the current viewer timezone. Google has no setting to switch this off. Normally this isn’t a problem when both the calendar and the viewer are in the same timezone.
Each calendar in Simple Calendar caches the events queried from Google for a period of time and updates them at periodic intervals. You can change the default maximum interval for each individual calendar, in the Advanced tab in the calendar settings panel. It is recommended you leave it at the default setting.