Using the Ignore Version allows you to open 2009 files in 2011, and 2011 files in 2009, correct? Will there be any problems going back and forth? I figure that for things that haven't changed between versions, it'll be fine, and anything done in 2009 will work in 2011, it's only if new features of 2011 are used, it won't open properly in 2009?
When you bring a file made in an older version to a newer version, it says "file created in older version, if saved, won't be able to open in older version", that's not true though is it, if you use "ignore version"?
Also, can I have both 2009 and 2011 installed on my computer?