Hi,
I don't know enough about Shiny server to see the issue, but I do know that all al these messages are just package messages and warnings that are standard when they get loaded.
The only place I think a real error occurs is here
/opt/shiny-server/scripts/shiny-run line 3: 26791 Aborted
I don't know what the error is, but at least it gives you a place to start looking...
Hope this helps,
PJ