I find these tenses particularly challenging in German, particularly when combined with the passive.

The robbers would have been able to get away and could have avoided being arrested, if they hadn't been noticed by a passer-by. Unfortunately for them, they were turned in, although they could have got away.

Die Raeuber haette entfeuchen konnen und haette vermeiden konnen festgenommen zu sein, wenn sie nicht wäre gesehen worden (could "nicht wäre gesehen gewesen" work?)

If i had enough time in the morning, my bed would have been made and the chickens would have been fed.

wenn ich ausriechend Zeit gelassen haette, mein Bett waere gemacht worden und die Huehner waeren gefuettert gewesen. 

The alarm should have been set for an earlier time, so that all of these things could have been acheived.

Der Wecker waere auf eine frueher Uhr gestellt worden sollen, damit alle diese Dinge waeren erledigen worden koennenhh 

I think that they will have been arrested

Ich meine, dass sie werden festgenommen worden sein