list index out of range

Heyy !!

I am very new to Madgraph (using the new version v2_6_7, and trying to test this RPV model. But I have a problem that I guess is not attached to this. Probably there is something missing ( like an install ... ). Here is what I get when I launch my process using >launch myprocess :
Command "launch myprocess" interrupted with error:
IndexError : [Fail 5 times]
  list index out of range
Please report this bug on https://bugs.launchpad.net/mg5amcnlo
More information is found in 'MG5_debug'.
Please attach this file to your report.

in the MG5_debug :
Traceback (most recent call last):
  File "/Users/mac/Madgraph/MG5_aMC_v2_6_7/madgraph/interface/extended_cmd.py", line 1514, in onecmd
    return self.onecmd_orig(line, **opt)
  File "/Users/mac/Madgraph/MG5_aMC_v2_6_7/madgraph/interface/extended_cmd.py", line 1463, in onecmd_orig
    return func(arg, **opt)
  File "/Users/mac/Madgraph/MG5_aMC_v2_6_7/madgraph/interface/master_interface.py", line 494, in do_launch
    return self.cmd.do_launch(self, line, *argss, **opts)
  File "/Users/mac/Madgraph/MG5_aMC_v2_6_7/madgraph/interface/madgraph_interface.py", line 6943, in do_launch
    ext_program.run()
  File "/Users/mac/Madgraph/MG5_aMC_v2_6_7/madgraph/interface/launch_ext_program.py", line 77, in run
    self.launch_program()
  File "/Users/mac/Madgraph/MG5_aMC_v2_6_7/madgraph/interface/launch_ext_program.py", line 634, in launch_program
    usecmd = ME.MadEventCmdShell(me_dir=self.running_dir, options=self.options, force_run=True)
  File "/Users/mac/Madgraph/MG5_aMC_v2_6_7/madgraph/interface/madevent_interface.py", line 2116, in __init__
    self.load_results_db()
  File "/Users/mac/Madgraph/MG5_aMC_v2_6_7/madgraph/various/misc.py", line 424, in deco_f_retry
    raise error.__class__, '[Fail %i times] \n %s ' % (i+1, error)
IndexError: [Fail 5 times]
 list index out of range

I can't really understand where to start to know where the problem comes from, so I thought maybe it was obvious to some of you.

Thanks in advance.

Douja.