She’s engaged in some hanky-panky with Han Solo in Hanover Street (1979). There are a few flashes of her breasts or butt in other films, but they are just that: brief flashes. This is the only time when she was just standing there, showing her fun stuff.
UPDATE from the comment section. (Author: The Snapper)
I’m pretty sure she was nude in a British TV biopic about a stripper called ‘The One and Only Phyllis Dixey’ but I’ll admit I can’t remember for sure because I haven’t seen it since 1978 when it played on TV.
Yup, you seem to be right. I’m trying to find a copy now. This is a screenshot (allegedly) from a workprint: