Problem running an example of SHiP with Dark photon

Hi maddump team,

I was trying to reproduce the exclusion plot for the dark photon model of the arxiv:1812.06771 (Figure 10).
For that I follow the example given at appendix D3 and download the repository which
contains the folder example_SHiP, where I found the model file , the .hepmc example file and the code.
While running maddump, I obtained an error just after the decay of the pion start.
I changed the .hepmc file and generate it with Pythia by myself, but the error still remains the same.

The code that I run in maddump is

import model DM_mesons_2
import_events decay example_MesonFlux.hepmc
decay pi0 > y1 a, y1 > xd xd~
define darkmatter xd
add process interaction @DIS
add process interaction @electron
output /path-to-madgraph/DP_electron
launch /path-to-madgraph/DP_electron
set flux_norm 2.0e20
set prod_xsec_in_norm false
set d_target_detector 5650.0
set detector_density 3.72
set off-axis false
set parallelepiped True
set x_side 187.0
set y_side 69.0
set depth 200.0
set ncores 4
set testplot True
set gvd11 -3.333333e-4
set gvu11 6.666666e-4
set gvd22 -3.333333e-4
set gvu22 6.666666e-4
set gvd33 -3.333333e-4
set gvu33 6.666666e-4
set gvl11 -1.000000e-3
set gvl22 -1.000000e-3
set gvl33 -1.000000e-3
set my1 scan1:[0.01*i for i in range(1,14)]
set mxd scan1:[0.01/3.*i for i in range(1,14)]
set wy1 auto

Before maddump stops appears:
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decay pi0 > y1 a, y1 > xd xd~
launch
INFO: Parsing input event to know how many decay to generate. This can takes few minuts.
INFO: Will use seed 231615588
INFO: generate 6280 decay event for particle pi0
INFO: Will use seed 241056385
decaying event number 100 [0.145751953125 s]
decaying event number 200 [0.301811933517 s]
decaying event number 300 [0.452730894089 s]
decaying event number 400 [0.601742982864 s]
decaying event number 500 [0.741159915924 s]
decaying event number 600 [0.880850076675 s]
decaying event number 700 [1.03992199898 s]
decaying event number 800 [1.19558405876 s]
decaying event number 900 [1.34993886948 s]
Exception :
Please report this bug to developers

           More information is found in 'debug'.

           Please attach this file to your report.
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In both versions ( 1.0.1 and 1.0.2 ) the error is the same.

I will appreciate any help you can provide me regarding this issue.

Best regards