Charley, you'r correct in saying there are a few variants of The Ball of K, Highland Gathering etc., but usually they're comprised of mainly bawdy verses sung in 6/8 time with different choruses .. the one we sang as youths(!)

Dance tae yer partner,
Arse against the wall,
If ye've never been fucked on a Saturday night,
Ye've never been fucked atall. ... Extremely rude.

The verse you quoted about the Royal family is from Johnny Lad, a more relaxed, 2/4 or 4/4 tempo. The chorus ..

And wae you, and wae you, and wae you , my Johnny Lad,
Ah'd dance the buckles aff my shin wae you my Johnny lad.

This song is not really vulgar as it was a Glasgow kids' street song. Verses about the Royal family crept in around the late fifties:
The Queen was in the parlour,
Eatin' bread and honey;
The Duke was in the countin' house,
Fiddlin' Scotland's money!