They used to be very creative with posters in the 70's and early 80's. Have you ever seen the Italian poster of "The Evil Dead"? (in Italian called "La Casa" meaning "The House") http://www.lazonamorta.it/UserFiles/Image/la_casa%201.jpg

As for the Buck Rogers clip, it was my understanding that Lucas simply wanted us to feel like being in a cinema of his youth (his "famous" matinées that he's always going on about), with THX1138 as a new serial being shown with advertising for a Buck Rogers episode at the start. Quite smart I have to say, because by doing so he also shows a difference between an adventurous, idealized (and relatively happy) future opposed to the oppressing future shown in THX... not necessarily meaning that they would be set in the same century. But maybe I'm reading too much into it!

However I also wonder if it's due to the excessive creativity of Italian dubbers, Warner Bros over-zealousness or (also possibly) a mistake by the Italian dubbers in saying centuries instead of years (that would set it in late 23rd Century).

No worries about the rest, I'm glad I could help and I'm very glad I can relieve myself from the burden of holding the only (as far as I know) existing copy of this THX edit... if my hard disc will ever fail I know that this rarity is at least safe in someone else's computer!