Allumeria Troubleshooting

The first pinned Steam thread after Early Access began 28 August 2026 was the developer’s own “If the game wont start” note. Same-day topics covered instant crash on launch, multiplayer not working, and fullscreen HDR. This page is a player checklist, not a support contract. It does not replace Steam’s verify tool or the system requirements page.

Will not start / instant crash

Work top to bottom. Retest after each step.

1. Confirm you launched the paid Allumeria app (3516590) if you bought 0.15, not a leftover demo shortcut (4247370). The demo stays on 0.14.x. Mixing shortcuts is how “nothing new happened” reports start.
2. Verify integrity of game files in Steam → Properties → Installed Files.
3. Update GPU drivers. Allumeria is a custom OpenGL client; stale drivers fail more often than the GTX 1080 line on the store page suggests.
4. Run Steam as administrator once. If that works, you have a permissions issue, not a missing voxel.
5. Disable Discord overlay, NVIDIA overlay, and HDR fullscreen. HDR complaints are already on the board; try windowed or borderless without HDR.
6. Add the game folder to antivirus exclusions. OpenGL indie titles get false positives.
7. Delete shader/cache folders only if the notes in Steam discussions name them for your build. Blind deletes without a backup waste more time than they save.

If the crash is a one-frame window then silence, check Event Viewer for OpenGL device lost. Then read specs again. The developer has said the Steam GPU row was his own machine. The demo is still the right test if you have not bought yet. See demo vs full game.

Multiplayer will not join

Co-op is Steam peer-to-peer. There is no server browser.

• Host must be in the world with Host Multiplayer enabled from the pause menu, not sitting on the title screen.
• Both players need to be Steam friends. Join Game from the overlay or the friend’s profile.
• Disable VPNs that break Steam Datagram.
• The host’s upload is the server. A strong GPU with a 3 Mbps uplink still feels like rubber.
• Demo guests in a snow world is a content mismatch, not a NAT bug. Host forest or wait until everyone owns 0.15. Full steps: multiplayer guide.

Merchant, doors, HDR, map

• Merchant not selling — housing, not a crash. Use NPC housing.
• Doors not blocking damage — standing in the doorway still counts as exposed. Step fully inside. Report leftover cases on Steam, but try a two-block foyer first.
• No world map — 0.15 has no minimap in the Minecraft sense. Use coordinates, painted lamp colours, and Spawn Pointer items. That is a design gap, not a missing file.
• Fullscreen HDR — turn HDR off in Windows or use borderless windowed until a patch lands. Watch patch notes.

After it runs

You do not need this page to craft a Flint Pickaxe. Go to getting started. If the world loaded and you are lost in snow, that is the Snow Dungeon walkthrough, not a driver issue. Keep a zip of the world folder before you verify files on a world you care about. Steam verify fixes binaries; it is not a backup.

Official channels for leftover crashes: Steam discussions (pinned troubleshooting), Discord on the links page, and the developer’s Steam news. This wiki will not host executables or “crash fixer” downloads.