Hello,
I use the following sentence to make text alignment to be vertical in my Chart.
chart.PrimaryValueAxis.TitleArea.TextRotationAngle = 90;
You can change the angle to make it to be horizontal.
Also, I show my method about creating chart in my blog, including text settings in Chart.
I think that my post may be helpful for you.
Post link:
http://janewdaisy.wordpress.com/2011...hart-in-excel/