Someone gave me an original Cockerill plate from one of these locomotives, so I had to have a model, of course!

I did build it as a working engine for actual broad gauge (19,2mm), which required a bunch of etched parts and a cnc-milled frame plus a very specific set of parts from the junk drawer, so I went with the easy option and just uploaded it as an all-printed static model and I'll leave it up to your creativity if you want to turn it into a runner. If you'd like to try that and feel it would be helpful to have the original rhino file just let me know!

Note: I uploaded wheels and chassis separately as I made a version for 16,5mm track so it will fit on standard H0 layouts and a proper scale version for 19,2mm track. I figured it would be very confusing to have those sets of parts together in 1 thing.

here's the broad gauge version:
https://www.thingiverse.com/thing:7426859

and the narrowed down standard gauge (16,5mm) version:
https://www.thingiverse.com/thing:7426873

some tips for printing:

boiler: vertical, supports on cab side
cab: tilted forward a bit, I already built in supports for all the complicated stuff in the cab so no need to worry about that
chassis (loco and tender): straight upside down, so supports on the top side.
tender sides straight up, made them a separate part to prevent printlines in between the rivets
wheels: supports on the back
rods: supports on the bottom
crosshead guides: straight up, supports on the back of the cilinder covers
front buffer beam: tilted back a bit

other stuff needed:
metal wire of various diameters (I used 0,25mm, 0,4mm, 0,6mm and 0,8mm) and metal sheet, 0,2-0,3mm brass for example
5 M2 nuts and bolts (if you don't want to just glue everything)

assembly:
see pictures. Yellow parts on pictures are metal wire and sheet. Boiler handrails can be fixed to the boiler with loops bent out of 0,25mm wire. The steps/ladders under cab and tender can be made using a drilling rig as shown in picture T15
If you want you can add a whole bunch of thin oil pipes along the boiler, see pictures of the real thing, and of course the usual, tools and coal on the tender etc.
Please let me know if there are any problems.

pics of the real thing:
http://trenesytiempos.blogspot.com/2019/03/historias-del-vapor-xcv-las.html
https://www.forotrenes.com/foro/viewtopic.php?t=66217#p552238

pics of my model (it's almost finished)
https://www.flickr.com/photos/floris_dilz/albums/72177720301057762/

If you print and build one posting a make would of course be highly appreciated!
Cheers,
Floris