Generating MadAnalysis5 default cards freezes and gets killed automatically

Hey!

I am trying to pair-produce a VLQ top partner X_5/3 using the model 4FNS_UFO from https://feynrules.irmp.ucl.ac.be/wiki/NLOModels website with the subsequent decays. I am using the syntax

import VLQ_v4_4FNS_UFO
define allsm = u c d s u~ c~ d~ s~ ve vm vt e- mu- ve~ vm~ vt~ e+ mu+ t b t~ b~ ta- ta+
generate p p > x x~ > t w+ t~ w- , ( t > b w+ , ( w+ > allsm allsm ), w+ > allsm allsm ), ( t~ > b~ w- , ( w- > allsm allsm ), w- > allsm allsm )
output out
launch
 shower = Pythia8
 set ebeam1 6500
 set ebeam2 6500
 set KXL1 0
 set KXL2 0
 set KXL3 0.1
 set KXR1 0
 set KXR2 0
 set KXR3 0
 set MX 1000
 set WX auto

and when I run the script, MadGraph gets stuck at "Generating MadAnalysis5 default cards tailored to this process" , freezing my computer and the whole execution gets killed automatically after about 15-20 minutes.
I tried to pass the decay of top quarks and W bosons to MadSpin which works to the point when MadSpin generates the full matrix element squared at which point the whole process gets stuck (no freezing of the machine) at

INFO: generating the full matrix element squared (with decay)
INFO: generate p p > x x~ > t w+ t~ w-, (t~ > b~ w- , w- > allsm allsm QCD=99), w- > allsm allsm QCD=99, w+ > allsm allsm QCD=99, (t > b w+ , w+ > allsm allsm QCD=99) --no_warning=duplicate;

where it takes about 20 minutes to finish after which the "Compiling Code" takes forever (at this stage I just kill the process).

I am wondering if the problem is just in the computational resources of my computer or rather if I am doing something wrong. I am using MadGraph5_aMC@NLO v2.6.7.

Thanks a lot!
Best,
Jakub