Hi @hiviz, this is due to the font. The "Bahnschrift" has been created from objects and has not been assembled as a path.
If you set the wireframe view in Xara, you can see that. Here is a screen shot from Xara and from Fontcreator Professional for clarification.

Click image for larger version.  Name: Clipboard 1.jpg  Views: 86  Size: 85.1 KB  ID: 133575 Click image for larger version.  Name: Clipboard 2.jpg  Views: 78  Size: 27.1 KB  ID: 133576

The PDF should be printable, if not or you don't like the view you have two options:
1. take another font
2. Convert the font into objects and connect each letter into one path