The "Durex" connotation (our name for sticky tape and the Poms' name for frangers) was known in Oz in my circles in the 50s, probably because of the influx of immigrants from Albion's Isle. But, because we had a high school teacher who'd been on a Fulbright Exchange to the USA we became informed about other, similar, confusions with American-speak.

He was teaching in a school with windows that didn't open (air conditioning was common in the USA then but unheard of in Oz school) and one of the girl students complained about being too hot (ah, for such innocent times); he suggested she take off her jumper and was surprised at the shocked reaction from the students. One took him aside and explained that he'd suggested she take off her dress. What an Australian understands by the word "jumper" in this context, is called a "pullover" in the UK and a "sweater" in the USA; he told us that what an American calls a "jumper" an Australian would call a "gym tunic". There was also a different understanding about the word "slated" that he described as well but that may have changed.

Leenia, when an Australian is "taking the piss", it is usually "out of something or someone" and a similar expression you might know is "taking the Mickey out of ....". It may be meant in fun, is a staple of satire, and may be even more pejorative.

Cheers, Rowan