I just have a test with ACE 3000 v6.3.3 and it seems the biggest concern to me now is HOW TO CREATE CORRECT DRILL FILE (.drl) from my DXF. When I tried, there is no information in the .drl exported. 1. To generate a drill file, you must select the "Flash" option when importing your DXF file. Why? ACE 3000 automatically generates the drill data based off of the "gerber flashes". Flashes contain a center point and diameter, so it is very easy for ACE 3000 to recognize and construct a drill file based off the flashes on a selected layer.
2. Here's a link to the ACE 3000 user forum on this particular topic:
Note: There are several topics on the ACE 3000 user forum related to this topic. In the future for more assistance, try typing a keyword like "drill" into the ACE 3000 edit box called "Need Help? Ask a Question..." (located at the top-right of the ACE 3000 screen). Press enter, and ACE 3000 will search the user forum and try to find answers for you.
3. By default during DXF import, ACE 3000 will only flash circles with a diameter of 175 mils or less. This is the default setting that is shipped with ACE 3000 and it is controlled by the setting "Flash Circle/Rects Less Than (mil)". Your circles appear to be 176 mils, so ACE 3000 doesn't create gerber flashes for your circles; and thus that's why your drill did not contain anything. To correct the problem you will simply need to increase the value of setting "Flash Circle/Rects Less Than (mil)" to a larger value like "250" (ACE will remember this setting adjustment, so you don't need to worry about it again). I have created a sample movie tutorial (no sound) showing how to successfully generate a drill file from your sample DXF: