The inst.stage2 parameter in the boot menu entries for Server DVD images produced by Pungi 4 looks like this: inst.stage2=hd:LABEL=Fedora-S-boot-x86_64-(version) this is incorrect. Note the '-boot-'. It should be '-dvd-'. Due to this error, the images do not boot. If you manually edit the cmdline and change -boot- to -dvd-, the images boot OK. Verified with https://kojipkgs.fedoraproject.org/compose/rawhide/Fedora-Rawhide-20160222.n.0/compose/Server/x86_64/iso/Fedora-Server-dvd-x86_64-Rawhide-20160222.n.0.iso and https://kojipkgs.fedoraproject.org/compose/branched/Fedora-24-20160224.n.0/compose/Server/x86_64/iso/Fedora-Server-dvd-x86_64-24-20160224.n.0.iso (so both Rawhide and 24). This is an automatic Fedora 24 Alpha blocker: "Complete failure of any release-blocking TC/RC image to boot at all under any circumstance - "DOA" image (conditional failure is not an automatic blocker)". We don't technically have a TC yet, but this issue would certainly affect one.
I believe the parameter is actually produced in lorax - in share/templates.d/99-generic/x86.tmpl , specifically - but I *think* the isolabel value that uses is ultimately passed in from Pungi. I tried to figure out how the Server DVD compose process actually works, but couldn't grok it, or find any relevant logs.
This seems to be resolved in the last few composes (both 24 and Rawhide), they're now reaching anaconda and blowing up on the glibc langpack problem.