Submitted a bug report - also posting here:

Started adventure - Stealing from the Rich - Wednesday night before maintenance (6-20) - Sent 4 generals, 3 regular, 1 vet, friend invited.

Logged on after maintenance - no floating box - could still access through quest menu - did a few camps (did not realize I could check the box to get the floating box back so not sure if that made a difference). Did a few camps, friend did a few camps.

This evening (6-21) I came back, did a few more camps, and was invited to friend's SFTR.

Now I am unable to access my adventure (no floating box - only friend's adventure showing in quest menu.
Two of my generals are still there.

However, my friend can still access that adventure, she is going to complete it so hopefully that will get my generals back - still thought you should know as this is a fairly serious glitch.