Hi, if you have a look at this post viewtopic.php?f=8&t=154
you will find two PDF documents you can download. Each document shows a different way to create a shadow mat.
I find Path>Outset is often better for fonts and shapes with square edges.
Path>Offset and Path>Dynamic Offset seem to round any straight corners but they work great if not adding to deep a shadow or for designs that are curvy.
Give a holler if the files on the other post don't help with your project.