In order to define a drilling operation you have to select the holes to be machined. Each hole is defined by two circles defining the bottom and the top level of the hole.
After pressing the Select Holes button the user is guided by a separate window through the selection process. At least two circles have to be selected. The circles have to be located in parallel planes. Furthermore, the normals of the planes going through their circles have to be coaxial. Otherwise the selection will fail.
After the operation has been defined it can be computed (computation of the tool path) using Process Plan Explorer – right-click on the operation and select Compute.
Have a look at Sample_3AxisDrilling.xml that can be found in the examples directory of TE installation.