Can't Change Line Width

[David Boothe]

I am new to this list, though not new to Lilypond.  However, I am by no means a 
Lilypond expert.

I have a template that I use for setting the weekly Psalm antiphons - a single 
line melody with lyrics on letter size paper in landscape mode.  It has always 
worked fine.

Recently I upgraded Lilypond to 2.12 (on Windows).  Now the width of the line 
is less than half the width of the page, causing the layout to be crowded, 
horizontally.  It readable, but not easily.

So I added this line to the layout block:

    line-width = #150

using various values for the number. Nothing changes.  I also tried

    line-width = 24\cm

but that produces an error at "\cm."

Increasing the staff size makes it larger, but does not change the width vs. 
height, so the layout remains crowded.

Any help appreciated.

Thank you.

-David.