FiveM map conflicts: fix flickering MLOs and missing props

You add a new MLO, restart the server and drive over to see it. The building is there, but the police station across town now flickers, a parking lot lost its lamps and one wall of the interior disappears when you walk up to it. Nothing in the console says why. This is a map conflict, and it is one of the most common problems on any FiveM server that runs more than a couple of maps. This guide explains where conflicts come from, how to tell which kind you have, and how to fix them without spending an evening in CodeWalker.

Why map resources conflict

Most maps don’t build the city from scratch. They edit pieces of GTA V that already exist: they move a fence, delete a lamp post that stands in the way, or cut a hole into the occlusion of a block so their interior shows up. To do that, they ship their own copy of a base-game file, with the same name as the original.

The trouble starts when two resources ship a copy of the same file. The game loads only one of them: the one from the resource that starts last. Everything the other map changed in that file is simply gone.

ensure pd_mlo
ensure burgershot_mlo
ensure street_lights

If both MLOs stream dt1_05_strm_1.ymap, only the copy from burgershot_mlo loads. The police station’s edits never reach the game, so its interior is drawn with the original block around it. Swapping the two lines doesn’t help, it only moves the breakage to the other map.

The kinds of conflict, and what they break

The file type tells you a lot about what you will see in game. These are the ones you run into most often.

Map flickering (occlusion conflict)

To save work, GTA V doesn’t draw what it thinks is hidden behind walls. Those invisible blockers are called occluders, and they live inside .ymap files. An MLO has to remove the occluders that would hide its interior. When another map’s copy of that file wins, the old occluders come back: the interior flickers, vanishes when you get close, or you can see straight through the walls into the void.

Prop placement conflict (.ymap)

A .ymap also says which objects stand where: buildings, props, LODs, lights, grass, even the spots where parked cars spawn. When two maps edit the same one and only one copy loads, you get missing props, buildings that pop in and out, lamps that don’t light up, or a tree growing through the middle of a new garage.

Archetype conflict (.ytyp)

A .ytyp defines the objects themselves: which model a prop uses, how far away it stays visible, and for MLOs, the rooms and portals inside. If two copies disagree, props show up with the wrong model or not at all, and an interior can lose a room.

Collision and 3D model conflicts (.ybn, .ydr)

A .ybn is collision: what you can walk on and what stops you. A .ydr is a 3D model. A clash here shows up as walking through walls, invisible barriers, falling through a floor, or a prop with the wrong shape or textures. These files are whole objects rather than lists of edits, so there is nothing to combine: you decide which copy should win and make sure that resource starts last.

Fixing it by hand

Until now, the usual fix looked like this:

1. Search every resource for files with the same name.
2. Open each copy in CodeWalker and compare them entity by entity.
3. Copy the props, occluders and lights from one file into the other, and delete what one map removed.
4. Save the result into a new resource, rename or delete the originals, and get the start order right.
5. Restart, drive to every place that changed and hope nothing else broke.

For a single file that’s an hour of careful work. A big server has dozens of them, and the moment one map gets an update you get to do it all again. It is also easy to get wrong: miss one occluder and the flicker stays.

Merge them in a few clicks

The Map Merger in the FiveDock desktop app does that work for you. It reads your server.cfg, finds every .ymap and .ytyp that more than one started resource streams, and folds each set of copies into one file that keeps every map’s changes.

1. Open Map merger in the desktop app and pick your server folder.
2. Click Scan. You see each conflicting file, the resources that ship it, in the order they start, and whether it can be merged.
3. Click Merge. The merged files go into a new fivedock-merged resource, and an ensure fivedock-merged line is added to the end of server.cfg, so it always loads last.
4. Restart the server.

The merge follows one simple rule, the same one you would follow by hand:

• Everything a map adds is kept. Every prop, light, car spawn and occluder that any of the maps brings in ends up in the merged file.
• Everything a map removes stays removed. If one MLO deleted a base-game occluder or a lamp in its way, the merged file leaves it out, even if the other map’s copy still had it. That is what stops the flickering.
• Edits to the same occlusion model are combined. When two MLOs each cut their own hole into the same occluder, the merged file has both holes.

Copies that are byte-for-byte identical are marked as such and skipped, since they can’t conflict. Distant LOD lights are merged together with their matching LOD light file, which the game needs to stay in sync. You can do the same from the command line:

> fivedock merge C:\server
41 started resources, 3 map files streamed by more than one
  dt1_05_strm_1.ymap  pd_mlo -> burgershot_mlo
  vw_distlodlights_medium010.ymap  pd_mlo -> street_lights
  shared_props.ytyp (identical)  pd_mlo -> burgershot_mlo

> fivedock merge C:\server --apply
  merged dt1_05_strm_1.ymap  +38 -4, base-game file
  merged vw_distlodlights_medium010.ymap  +112 -0, base-game file

Wrote C:\server\resources\[fivedock]\fivedock-merged. Undo with: fivedock merge undo

+38 -4 means the merge brought in 38 items the first copy didn’t have, and left out 4 base-game items that one of the maps had deleted.

When a map gets an update, run the scan again. The merger also reads its own earlier output, so the new copies are folded into what you already have.

When you don’t need to merge

A file streamed twice isn’t always a problem. Leave it alone when:

• both maps look right in game. Not every shared file holds something either map depends on.
• the copies are identical. The merger marks them and skips them for you.
• the conflict is in a .ybn or .ydr. Pick the copy you want and adjust the start order instead.

Common questions

Why does my MLO flicker or disappear when I walk up to it?

Usually because another resource streams its own copy of the same .ymap, and that copy still holds the occluders the MLO removed. GTA V does not draw what an occluder hides, so the interior flickers or vanishes as you get close. The game loads the copy from the resource that starts last.

Does changing the ensure order fix FiveM map conflicts?

Only for collision (.ybn) and model (.ydr) files, where you pick the copy you want and make its resource start last. For a .ymap or .ytyp that two maps both edited, the game still loads one copy, so a new order moves the breakage to the other map. Those files have to be merged into one copy that keeps both maps’ changes.

How do I find which resources stream the same .ymap?

Look for files with the same name in the stream folders of every started resource: two resources that both ship dt1_05_strm_1.ymap conflict over it. The Map Merger in the FiveDock desktop app reads server.cfg and lists every .ymap and .ytyp that more than one started resource streams, in the order they start.

Can I merge .ybn or .ydr files?

No. A .ybn is a whole collision mesh and a .ydr a whole 3D model, so they hold no list of separate edits to combine the way a .ymap does. Decide which copy should win and make sure its resource starts after the other one.

Which plan has it

The Map Merger is part of the Metro plan. The scan and the files stay on your machine; the merge itself runs on FiveDock’s servers, so the app stays small and every merge uses the same, up-to-date data about the base game. Compare the plans or download the desktop app to scan your server.