Sorry for this delayed reply.
Thanks for the images! Just to confirm, the PowerBlock needs to have the USB micro connected to the PowerBlock PCB.
To rule out any software configuration issue, you could try and load this RetroPie 4.6 image that already comes with a readily installed PowerBlock driver: https://www.petrockblock.com/wp-content/uploads/2020/05/retropie-4.6-rpi2_rpi3-powerblock.img_.gz

In addition, I would suggest to remove any USB device except a keyboard to be sure not to get any interference from an USB device. The overall goal I have in mind with these actions is to find a stable status with a working PowerBlock.

Can you give me an impression until which point the boot sequence comes?

@xmrdarky Can you please fill in the information as requested here (https://retropie.org.uk/forum/topic/3/read-this-first) so people on the forum can try and help. Each setup can be wildly different and knowing all this goes a long way to assisting. Like @rbaker says, it sounds like it could be a power issue if you are running it just off a USB charger, such as a phone charger, but we wont know unless you give details.

What's the switch' part number? Where did you get it from? Maybe a little research can show how the switch LED is connected internally.
When you mentioned LED, is that the LED connected to the Contolblock or the LED on the switch?