PC x64 version in pendrive boots in legacy boot but not in UEFI... but I can force it to start (¡?)

[mundodisco]

Hi everyone,

I have found out that the Recalbox PC version (x64) that I have in my pendrive, boots just fine in legacy mode. But if I switched to UEFI bios, the boot starts but EmulationStation does not start.
The interesting part is that the web server is started (so I can access and monitor and change options, from another PC). AND (this is the most disconcerting part), if I go to help section and start EmulationStation, it runs just fine.
So, the question is... why EmulationStation is halting from open automatically if booted in UEFI mode (but can run manually), and it does open fine automatically if the pendrive is booted in legacy mode?
I have tried with two different pendrives, same result.
The PC is a Dell OptiPlex 790, latest bios version.

Regards,
Gabriel

[Zing]

@mundodisco It is recommended that you use Legacy mode, but, you can get a more detailed explanation on how to work in UEFI mode, in this topic:
https://forum.recalbox.com/topic/17464/dualboot-recalbox-windows-sur-pcs-laptops-avec-bios-ou-uefi-27-04-19?_=1585857631180
I had already recommended reading this topic to you: https://forum.recalbox.com/topic/20672/grub-and-boot-questions?_=1590094003287

I know the focus of the post is to do a dual boot, but there is a lot of useful information in it, and, as I said, the recommendation is to use legacy mode, not UEFI.