There is only one moment where we see Ripley's bare buttocks after he strips down while changing into a suit. He also wears extremely form-fitting swimming trunks.

We see quite a few paintings of a nude woman and some scenes last for several seconds.

We see a man getting undressed and dressed again. Full rear male nudity. Nothing else.

A few brief instances of grisly beatings.

Characters drink alcohol and smoke cigarettes.

Implausibly, Marge does not smoke cigarettes.

A character falls from a moving boat and nearly drowns when the boat's anchor hits him in the head.