Sorry to come in late to this thread, but I was just browsing old threads and saw you mention that you often have to "manually break lines".
Do you know you can do this by inserting "discretionary hyphens" at suitable points in the words you want to break (Command-hyphen on a Mac, presumably Control-hyphen under Windows).
This causes Quark to hyphenate at the point indicated (or the last one that fits if you put several in the same word) but in a "soft" way so that if the line later reflows due to other edits, the hyphen and line-break miraculously disappear!
Also, the "soft-hyphenated" word appears in spellchecking as if it had never been broken.
At least, this all works for me (even if hyphenation is "off" in Edit H&J's) up to QuarkXPress 6.5, Mac, International English.
Hope this helps. PHILIP