Madspin stuck in decay

Dear experts,

I am running a Madgraph production of electroweak production of WZ+2jets events in the 4 flavor scheme, at LO, this is the process definition:
process = """
import model sm
define p = g u c d s u~ c~ d~ s~
define j = g u c d s u~ c~ d~ s~
generate p p > w+ z j j QCD=0
add process p p > w- z j j QCD=0
output -f
"""
The decay is handled with Madspin. However, the generation seems to be stuck after the message “INFO: Decaying the events…”.
here are the Madspin settings:

set Nevents_for_max_weight 75
set BW_cut 15
set max_weight_ps_point 50
set seed %i
# specify the decay for the final state particles
decay w+ > e+ ve
decay w+ > mu+ vm
decay w- > e- ve~
decay w- > mu- vm~
decay z > e+ e-
decay z > mu+ mu-

I have tried several options for max_weight_ps_point and Nevents_for_max_weight and also tested the generation/decay with only one channel (generate p p > w+ z j j QCD=0), but no success so far.
Is there anything I am missing? Thanks!
Cheers,
Angela