Hello,
You can download the latest versions of Dynamic C 10.72 from the below link
http://www.digi.com/support/productdetail?pid=4978&type=documentation
Here you can find "Dynamic C 10.72" under "Development Software and Sample Code"-->General Software.
Also install “DC10.72 tcp patch” and “Dynamic C NAND flash library patch”.
You can find the above patches under "Development Software and Sample Code"-->Patches.
Thanks.