It prompts you to save the file in Corel (because it actually makes a copy of the file to run the processes on). After you save the Corel file, in the DXFTool Window, select where you want the DXF saved to. Then just hit the DXF Export button and you will get a progress bar and a window that tells you how many objects were exported. If you don't, then make sure you have validated the demo license in the License tab. If you get an error then DXFtool has found things that won't export right. One common problem is to have a node in a chain looped over itself (hard to find) or two chains overlapped (not welded). Those two types will display fine in Corel and even fill, but won't work for a CAM program and CNC.
You are welcome to send me the CDR files if they won't convert and I will tell you what's wrong with them.
Tom Caudle
www.CandCNC.com