Still struggle to sync

Experienced repeated problems with the Pro version I paid for. Would not sync with Google Calendars using two-step verification security on my Google account. Now, since iOS update, Tiny Calendar Pro no longer sends event invitations or updates to my husband, although it accepts his email address and seemingly has him on the invite list. He has not received one of them for two weeks.
New crashing problems every time I open it since April 26, 2016. Also not syncing some events with Google calendar while it does others.

Mtviewca about Tiny Calendar: Planner & Tasks