Might be interesting to see if they're incomplete in our search engine. What server are you downloading headers from?
Am using newshosting. Think you may be missing the point here. They are incomplete at the time I opened the group and of course time for the servers to get all the parts due to still being uploaded like within the past hour.
It's when I come back in say a couple of hours after another update of headers, I get the remainder of the files that were not showing earlier and they are all complete. It's the ones that showed incomplete 2 hours ago, do not change and keep showing as incomplete. I tried special dl and go for every option, and still no change. I have to dl all headers from this small group once more, and then all the files come in completed. It's kinda like I jumped in too early as this poster generally uploads on 2 or 3 consecutive days. They are mostly apk files, so usually not that large other than the obb folders.
Now if I haven't jumped into the group early, I always get all the files as completed. It's just jumping in while still being processed by servers, so I wait several hours before going back and the previous incompletes always remain incomplete till I dl all headers for that group over again. Sorry for repeating myself somewhat.
Hope I explained myself properly.