At last Canon released webcam support for professional dslr/mirrorless camera, but it's coming with new problems.
There is three type issues:
Due of high current demand sometimes user can't pass splash screen below.
Some third party batteries can't supply enough power so you can use desktop pc backside usb ports will supply enough current.If you are using laptop usb port , eos webcam utility may not work.Some laptops have a high current USB charging downstream port (USB CDP) port.USB CDP port can supply 1.5Amp. which is indicated a smaller thunder logo near by port.
Another option is powered usb hub/splitter.Non-powered usb hub won't work.
Otherwise you must use dummy battery for plugging wall outlet.
Eos webcam utility isn't a device driver, it won't list as a camera hardware in device manager , it will listed as a portable devices due PTP protocol using only image files transfers.It work as Directshow interface between applications(Skype,Zoom etc.) and Canon EOS SDK.EOS webcam utility work with only Directshow supported applications.
Universal Windows Platform (UWP) application like Skype, Camera which came installed in Windows 10 can't work. But Skype Desktop Edition and most of classic windows desktop application can work.Some 64 bit application like OBS(Open Broadcaster Software) isn't working now, but 32bit version OBS is working.Possibly it's a software glitch, will be resolve next releases.And some old application didn't worked Amcap8, but Amcap 9.23 work with some flaws.
And don't forget close Eos utility from system tray before using webcam function.
Eos webcam utility or any application using on EOS SDK can't offer more than 1024*576 resolution, it's a software limit.But Dslr cameras was not to be designed for video streaming devices so most of them don't comply with UVC(Usb video class) requirements in hardware.USB connection aimed for Still Image Capture Device function using PTP (Picture Transfer Protocol).
For live streaming camera push thirty jpeg image frames to usb bus, at the computer side jpeg files converted a Mjpeg video.Mjpeg videos well known for image quality and sharpness came with cost of data amount.Same time EOS sdk don't support hardware acceleration and it's resulted huge cpu usage and fan noise.
USB 2.0 port can transfer 1080@30fps and computers have enough process power.But we don't know inside of every camera.
Shortly , you can't get 1080p over usb now, further some cameras may achieve this resolution(not hopefully).