I try to evaluate Fluent.Ribbon for my application and at the moment I have many problems. It's not always so easy to reproduce these problems with small test applications, but here is one:
Title="MainWindow" Height="600" Width="800">
<TextBlock>Text to display</TextBlock>
Is seems that the TextBlock is drawn with a very low resolution and then zoomed to fit the free space.
If I make my MainWindow derive from System.Windows.Window the problem is gone and the TextBlock is drawn very accurate.