Back around 2015 when UEFI BIOS were just becoming a thing -- several months before the 1st Win10 beta came out -- the bootable USB sticks from Paragon's HDM couldn't really handle UEFI, especially a then new tablet with 32-bit UEFI BIOS. Not much could, including Backupper -- that's when I migrated to Macrium Reflect, which worked with UEFI pretty much perfectly. Come January 2023 however, Macrium Reflect Free is going away. Well, it's been roughly 7 years, so it would be reasonable to think that AOMEI would have had their bootable USB sticks working by now... that would be wrong. They do understand how this stuff works, because the Windows To Go drives you create with their Partition Assistant handle UEFI & Secure Boot just fine. I tried different USB sticks, Win10 & 11, downloading the ADK through the app etc., all with no luck. I didn't see anything in their FAQ, but when I Googled I found an AOMEI forum post from 10/2022 saying you need to disable Secure Boot & enable CSM. :( How 2015ish.
It IS possible to make your own bootable USB stick for Backupper, *If* you want to put in the work. You first have to install the ADK [3 or 4GB] from Microsoft to set up the WinPE working folder. Then using the ADK's Deployment & Imaging Tools Environment [a special Command Prompt] you mount the WinPE image, then in File Explorer copy the files from C:\Program Files (x86)\ AOMEI\ AOMEI Backupper\ 7.1.0\ Winpe64\ to a new folder in the mounted image. [Make sure you run that WinPe version of Backupper 1st & activate it as necessary before copying.] Now you create a new text file named Winpeshl.ini, add the command to start Backupper, and save it to the Windows\ System32\ folder in the WinPE image. Next you save / commit the image and dismount it, finally creating a new bootable USB stick. Alternatively, you can just copy the same Backupper files to a folder on a WinPE USB stick you've created -- WinPE will give you a command prompt, and you'll use DOS-type commands to navigate to the folder with Backupper & call / start the Backupper exe file.
learn.microsoft[.]com/en-us/windows-hardware/manufacture/desktop/winpeshlini-reference-launching-an-app-when-winpe-starts?view=windows-11
learn.microsoft[.]com/en-us/windows-hardware/manufacture/desktop/winpe-create-usb-bootable-drive?view=windows-11
learn.microsoft[.]com/en-us/windows-hardware/manufacture/desktop/winpe-mount-and-customize?view=windows-11#add-a-startup-script
Like Macrium Reflect, Backupper stores your backup archives in a proprietary format -- Paragon HDM is the only one I'm aware of that lets you use common VHD file formats. The GUI suffers a little bit from Ashampoo syndrome, where in trying to make it easy they actually make it harder to find what you're looking for if you know what you're doing. Otherwise it handles the basics OK, though you won't find any of the tools Macrium Reflect has for converting to, booting, or otherwise working with VMs, but most wouldn't use that stuff anyway.