Hi EdwinHz
"Could you try using the default USB/UART connection via J23"
Yes. This was the connection that I used to simulate the example "evkmimxrt1024_lpuart_polling example". I used in Debug and Release.
"Also are you using Windows 11?"
Yes. I am using Windows 11.
This is the EVK key that I am changing to put in Serial Download or FlexSPI Boot

I made some measurements with an oscilloscope and put the images below:
1 - UART of the iMX RT1024 EVK.
EVK turned on with SW8(10 - FlexSPI Boot) working with the code of the evkmimxrt1024_lpuart_polling example

2 - UART of the iMX RT1024 EVK
EVK turn off with SW8(01 - Serial Download) and app blhost.exe sending ping command


3 - UART of the iMX RT1024 EVK
EVK turned on with SW8(01 - Serial Download) and app blhost.exe sending ping command


Apparently, when the EVK is turn on, connected in UART and configured in Serial Download mode, app blhost.exe isn´t sending the ping command.
Please, let me know if you would like any more information