There are patches available for the Fx3 Debugger to address issues with OS X Sierra (10,12) and OS X High Sierra (10,13).
If you contact Absoft Support at the standard email address or through the form on the Absoft website, they can provide you with the correct download link. Be sure to include the Absoft version you using in your request. You can determine the full service pack version for your compiler by examining the file named absoft_release in your /Applications/AbsoftXX.X folder or by using the About AbsoftTools... command. Support will need to know the Absoft Pro Fortran version not the version of AbsoftTools.