Thanks dude,
I also manged to install it on Proxmox 5.3-7 and find small error in step 3:
"** example: qm importdisk 100 /var/lib/vz/images/100/vm-100-disk1.qcow2 <your-qve-disk>"
should be:
"** example: qm importdisk 100 /var/lib/vz/images/100/vm-100-disk-1.qcow2 <your-qve-disk>"
according to example in previous step.