This is an amazing theme--so glad I found it! I made a donation.
My blog is http://Culture-and-Current-Affairs.com
I searched the forums for "main column width" and similar search terms and thoroughly read about 25 posts and an article but did not see an answer to my question (not that I couldn't have missed it--my apologies in advance if I did).
Here's my question ...
Under Layouts > Default Sidebar Layout, I have selected 1(One) sidebar, postioned Left.
Under Widths > Default sizes / margins for page elements, I selected "Custom sizes and margins"
Under Page Width Type, I selected "Fixed width"
Under Fixed width settings > Overall Page Width, I selected "Custom width, but constructed from individual componenets"
Under Custom component width-Custom value for main column width, I typed in "875"
Under Sidebar width settings > Custom component width-Custom value for width of first sidebar, I typed in "275"
I also tried "900" and "300" for the above two values.
Either way the sidebar width and the main column width do not change.
My goal: Have the Main Column be about three (3) times as large as the sidebar and to not have much space (padding) between the two (maybe 25 px?).
P.S. I also:
Deactivated all plugins except Askimet.
Removed all the widgets I had on the sidebars (from a previous theme).
Reset most of the Suffusion settings to their defaults.