I'm having issues loading the live dvd from Mageia 7 or 7.1. Is anyone else experiencing this problem?

Give some info on the problem that you are having. Are you getting an error message? Is it stopping at the grub menu? What problem?

Need more info, what medium is live iso on, how did you put live iso onto medium

I do have the same issues. Live DVD from Mageia 7.1 does not boot from an usb connected external dvd drive. It only boots from a sata connected internal dvd drive. Does anyone know a solution to this problem?

Try to set usb as first boot device in your BIOS.
Otherwise it is possible that you need to load a specific driver for your external device.

Of course in BIOS usb is set as first boot device.
And I think it is very unlikely that any specific driver is needed. Standard USB-2.0 port. Linux Kernel does support that out of the box.

I've tested about 20 different Distros. No problems at all booting those from a burned DVD after downloading the .iso and burning it with Xfburn or Brasero. Only two distros failed to boot this way, Mageia and GhostBSD. I've no clue why. But when I tried booting on another computer which had an internal built-in DVD-drive, booting was possible when I use the internal drive which is internally connected to the sata or ide port. But as soon as I use the same DVD with the external drive which I connect to a standard USB-2.0 port, the boot process of Mageia Live DVD fails. But other Live DVD distros like CentOS, Debian, Slackware, OpenSolaris etc, then I can boot from that same dvd drive without any issues. So it must be something special to Mageia. I remember when I tested Mageia 6 a couple years ago there was the exact same problem.

That sounds a bit like a timing problem, like there used to be when trying to boot from USB originally, we needed to add a wait 5 seconds to the startup scripts - no idea if this would work on CD/DVD.