The file 'war3mapmap.blp' file is not a BLP file, it is a TGA file and should have the path war3mapmap.tga
instead of war3mapmap.blp
.
So if you rename it, everything should work. Also. Does this work in Warcraft as is?
That's incorrect. What you are referring to is the map preview "war3mapPreview.tga" which is in .tga. "war3mapMap.blp" is the minimap displayed in the bottom left during the game and it is blp. Since the reforged launcher can't display .tga, it displays the "war3mapMap.blp" which is why many mapmakers use it as an alternative to show a preview image in reforged these days.
Also since reforged does not care about the ending either being .blp or .dds for any texture that supported .blp before, I only have a wa3mapMap.dds file in my map and no war3mapMap.blp nor war3mapPreview.tga. Your parser tries to extract a file which does not exist, that is the problem here. Epicwar has the same restriction.
@Frotty, can I see your map?
I already linked you to the download page on maps reforged, where I can successfully upload the map. But attached also for your comfort.
That minimap would never have worked on the site at least. It's erroneously named.
It's not about the minimap failing to be displayed by the hive, it's about the map upload causing an internal server error because it's trying to extract something and fails. Imho you should either show a requirement error or simply lift the requirement and accept maps which are playable with the reforged client.