Problem: when setting the rotation property on a Flex label or text component the component becomes invisible.

Cause: To rotate text in Flex the font must be embedded.

Easy Solution:

1. Embed a system font in your Application like so:

[Embed(systemFont='Verdana',  fontName='myPlainFont',  mimeType='application/x-font' )]
private var font1:Class;

2. set the embedded font as font family for the text component you want to rotate, e.g:

l = new Label() ;
l.setStyle("fontFamily" ,"myPlainFont") ;

3.  set rotation ( e.g. l.rotation = 90 ) -  now the label should be rotated by 90 Degrees and visible.

Reference: http://livedocs.adobe.com/flex/3/html/help.html?content=fonts_04.html