[jbacelar]

Unfortunately it doesn't work with the new command either.
Attached (in case it is of any use) the debug log.
Thanks again for the try.

Spoiler:

C:\Users\JB>calibre-debug --edit-book
DEBUG: 0.0 GetFileName::__init__.py - loading translations
QPA platform: windows
devicePixelRatio: 1.25
logicalDpi: 96.0 x 96.0
physicalDpi: 75.3173745173745 x 75.25925925925925
ApplicationPaletteChange event ignored
Using calibre Qt style: True
ApplicationPaletteChange event received
qt.webenginecontext:
GL Type: disabled
Surface Type: OpenGL
Surface Profile: CompatibilityProfile
Surface Version: 4.5
QSG RHI Backend: OpenGL
Using Supported QSG Backend: yes
Using Software Dynamic GL: no
Using Multithreaded OpenGL: yes
Init Parameters:
* application-name calibre
* browser-subprocess-path C:\Program Files\Calibre2\app\bin\QtWebEngineProcess.exe
* disable-features ConsolidatedMovementXY,InstalledApp,BackgroundFetc h,WebOTP,WebPayments,WebUSB,PictureInPicture
* disable-gpu
* disable-speech-api
* enable-features NetworkServiceInProcess,TracingServiceInProcess
* enable-threaded-compositing
* in-process-gpu
* use-gl disabled
Editor chains: _get_plugins_resources(): start
Editor Chains: _get_plugins_resources(): finished
calling method (on_modules_update) of obj (Tag Actions)
Editor Chains: Tag Actions: running on_modules_update()
calling method (on_modules_update) of obj (Style Actions)
Editor Chains: Style Actions: running on_modules_update()
Editor chains: _call_plugins_on_modules_update(): start
Editor Chains: _call_plugins_on_modules_update(): finished
Editor Chains: SettingsWidgetDialog: Falling back to old constructor call
Editor Chains: Starting chain: Comprimir imágenes
Editor Chains: Comprimir imágenes: starting action No. 1: Run Command
Command error: Return code is 1 when running command for file: OEBPS/Images/autor.jpg
Command error: Return code is 1 when running command for file: OEBPS/Images/Figura_01.jpg
Command error: Return code is 1 when running command for file: OEBPS/Images/Figura_02.jpg
Command error: Return code is 1 when running command for file: OEBPS/Images/Figura_03.jpg
Command error: Return code is 1 when running command for file: OEBPS/Images/Figura_04.jpg
Command error: Return code is 1 when running command for file: OEBPS/Images/Figura_05.jpg
Command error: Return code is 1 when running command for file: OEBPS/Images/Figura_06.jpg
Command error: Return code is 1 when running command for file: OEBPS/Images/Figura_07.jpg
Command error: Return code is 1 when running command for file: OEBPS/Images/Figura_08.jpg
Command error: Return code is 1 when running command for file: OEBPS/Images/Figura_09.jpg
Command error: Return code is 1 when running command for file: OEBPS/Images/Figura_10.jpg
Command error: Return code is 1 when running command for file: OEBPS/Images/Figura_11-1.jpg
Command error: Return code is 1 when running command for file: OEBPS/Images/Figura_11-2.jpg
Command error: Return code is 1 when running command for file: OEBPS/Images/Figura_12.jpg
Command error: Return code is 1 when running command for file: OEBPS/Images/Figura_13.jpg
Command error: Return code is 1 when running command for file: OEBPS/Images/Figura_14.jpg
Command error: Return code is 1 when running command for file: OEBPS/Images/Figura_15.jpg
Command error: Return code is 1 when running command for file: OEBPS/Images/Figura_16.jpg
Command error: Return code is 1 when running command for file: OEBPS/Images/Figura_17.jpg
Command error: Return code is 1 when running command for file: OEBPS/Images/Figura_18.jpg
Command error: Return code is 1 when running command for file: OEBPS/Images/Figura_19.jpg
Command error: Return code is 1 when running command for file: OEBPS/Images/Figura_20.jpg
Command error: Return code is 1 when running command for file: OEBPS/Images/Figura_21.jpg
Command error: Return code is 1 when running command for file: OEBPS/Images/Figura_22.jpg
Command error: Return code is 1 when running command for file: OEBPS/Images/EPL_logo.png
Command error: Return code is 1 when running command for file: OEBPS/Images/ex_libris.png
Editor Chains: chain (Comprimir imágenes) finished in: 0:00:00.385428