I can view all my activites on my dashboard - but once I click on the activity to see more details I get "Unfortunately Connect has stopped working

1. Same here. Have you got a solution to this problem? 

I think that problem was solved. On my device everything start working ok again

See this thread: https://forums.garmin.com/apps-software/mobile-apps-web/f/garmin-connect-mobile-andriod/223310/connect-app-closes-down-when-i-attempt-to-open-an-activity-such-as-running-or-cycling/1052995#1052995