Hi, I tried your generate command, and got this: MG5_aMC>generate g g > h NP=2 QED=1 QCD=2 [QCD] Interpreting 'QCD=2' as 'QCD<=2' Interpreting 'QED=1' as 'QED<=1' Interpreting 'NP=2' as 'NP<=2' Order QCD is not constrained as squared_orders. Using: QCD^2=4 Order QED is not constrained as squared_orders. Using: QED^2=2 Order NP is not constrained as squared_orders. Using: NP^2=4 --------------------------------------------------------------------------- No Born diagrams found. Now switching to the loop-induced mode. Please also cite ref. 'arXiv:1507.00020' when using results from this mode. --------------------------------------------------------------------------- Interpreting 'QCD=2' as 'QCD<=2' Interpreting 'QED=1' as 'QED<=1' Interpreting 'NP=2' as 'NP<=2' 1 processes with 12 diagrams generated in 0.137 s Total: 1 processes with 12 diagrams then, at the output, got … INFO: Generating Feynman diagrams for Process: g g > h NP<=2 QCD<=2 QED<=1 [ noborn = QCD ] Command "output " interrupted in sub-command: "output" with error: KeyError : 1 Please report this bug on https://bugs.launchpad.net/mg5amcnlo More information is found in 'MG5_debug'. Please attach this file to your report. File "/Users/marcozaro/Physics/MadGraph/3.2.0/madgraph/interface/master_interface.py", line 313, in export return self.cmd.export(self, *args, **opts) File "/Users/marcozaro/Physics/MadGraph/3.2.0/madgraph/interface/madgraph_interface.py", line 8278, in export calls += self._curr_exporter.export_processes(self._curr_matrix_elements, File "/Users/marcozaro/Physics/MadGraph/3.2.0/madgraph/iolibs/export_v4.py", line 198, in export_processes calls = calls + self.generate_subprocess_directory(\ File "/Users/marcozaro/Physics/MadGraph/3.2.0/madgraph/loop/loop_exporters.py", line 3343, in generate_subprocess_directory export_v4.ProcessExporterFortranMEGroup.generate_subprocess_directory( File "/Users/marcozaro/Physics/MadGraph/3.2.0/madgraph/iolibs/export_v4.py", line 5734, in generate_subprocess_directory self.write_coloramps_file(writers.FortranWriter(filename), File "/Users/marcozaro/Physics/MadGraph/3.2.0/madgraph/iolibs/export_v4.py", line 5982, in write_coloramps_file lines.extend(self.get_icolamp_lines(subproc_to_confdiag[subproc], File "/Users/marcozaro/Physics/MadGraph/3.2.0/madgraph/iolibs/export_v4.py", line 1160, in get_icolamp_lines bool_list = [(i + 1 in diag_jamp[num_diag]) for i in range(colamps)] File "/Users/marcozaro/Physics/MadGraph/3.2.0/madgraph/iolibs/export_v4.py", line 1160, in bool_list = [(i + 1 in diag_jamp[num_diag]) for i in range(colamps)] KeyError: 1 Are you sure that you want to generate a loop-induced process? Marco > On 19 Apr 2021, at 15:05, Gangcheng Lu