I will do my best but help is always welcome.

 You move first then the 9 major AIs move and then the 8 minor AIs move next. Ok, at the top middle of the map in ToA game, it has a date like 8 jun 2230, that changes every turn like 7 days at a time.  I think the green light on the TURN means you have no more ships to move.

Click on the MENU and it will take you to OPTIONS then click on GAME find Ship Movement. I check " Allow game to select next ship left with moves"

Guard is, I think help me if I am wrong, move a fleet of ships onto a star base then click Guard so that any ships will attack your fleet first.

Sentry is, I think is when a a ship gets into sensor range it activates telling you that a ship is near by and its ready for new orders.

I copy and paste this from the Twilight Manual

Sentry:

This tells a ship to be idle until another ship - friendly or en-emy - comes near.

Guard:

This tells the ship to sit idle until an enemy ship comes near.

By the way are you interested in joining an Empire if so go to Forums then click on Metaverse there you find Empires that are active, I would not want anybody to join a dying or dead one. I would join one that is in the top ten, Oh by the way. I have an Empire you should read about, click on the link below to take you to my empire. You know you can do whatever you want to do because you have a choice.

We are looking for players to join to be aggressive Admirals to lead my fleets across the Galaxy.

Saint Mina of Ophelia VII of Order of the Bloody Rose of Orders Militant of Adepta Sororitas

Maybe this will help you out.

There is this "Find" button that you can use. When you click on it the camera in the game moves directly to the ships that have no orders. And when the "Turn" button get a green lit around it means that all ships have their given order. If it not lit green then it means you have ships with movements left. There is an option that let you make all the ships movement even if you have clicked the turn button. Does auto-pilot get than a chance to use all its movement before the turn.

Do you want to make an alliance with other nations? Then you simply need a good relationship and a technology called "Alliance" (techs with yellow color). The relation have to be "close" for an possibly to make an alliance, though some nations (mighty nations) can be harder to preausade an alliance with for some reason.

I guess sentry mode let your ships watch out for enemy ships. From where your sentry ship can see an enemy ship arrive it will let you know by moving the camera to its location.

/ Have a good one!

You can set the relationship with the other races to "Team", if it that you mean?

I'll have to check on the 'team' setting.  I've had an alliance early in the game every time I've played so far, one I didn't seek, once with the bloody Dreghin. 

Go figure.