That is not really a Corel, DXF problem. It will happen even on parts you draw in Plasmacam.
Picture a triangle, take one side and move it toward the center. Now take the other side and move it toward the center. Neither line got shorter when you did that. So you end up with a X at the end where they intersect. Plasmacam connects the two lines with with a short line to keep it one cut path.
You have five options (that I can think of)
1. Convert it and trim all the corners, time consuming but if you are going to cut it out many times it will be worth your time.
2. Change your offset distance to 0. The down side is the part won't be the exact size you may have intended it to be. But on artsy stuff it really doesn't matter. This is the fastest and most used option.
3. Scale the size of the part up really big, then convert it. Downside is the pierce length and gap at end of loop will change when you scale it back down to the correct size.
4. When you draw something radius the corners. The line will offset and the radius will get smaller or even disappear.
5. Don't worry about it. Chances are unless the cross in the corner is huge, you probably won't even notice it. Remember its plasma not Laser.  |