I have gns3 working fine on my laptop. The IOS are all genuine as I have cisco contract.
I also have VIRL. I am setting up some Docker labs so I need more power so I am using PACKET.NET.
but when I try to use a genuine IOS on the remote server in packet I get this message please use only a filename in /opt/gns3/images/ios
Doing a preliminary search on Google, it seems that this is a bug. You may need to upgrade. Take a look at this thread about the bug:
I hope this has been helpful!