Yes – Right-click → Options → Calendar → Show week numbers.
Yes – sync via Google Calendar or store the .ics file in Dropbox (but don’t open same file from two computers simultaneously). rainlendar user guide
1. Introduction to Rainlendar Rainlendar is a lightweight, feature-rich desktop calendar and task manager available for Windows, macOS, and Linux. It stays on your desktop (or as a floating window) and supports skins, multiple calendars, online synchronization (Google Calendar, Outlook, CalDAV), and event alarms. Yes – Right-click → Options → Calendar →