On my server running Forge 1558 and latest BC + BC Compat versions (7.1.14 and 7.1.3), I have many problem with clients suddenly freezing when approaching a location in the map.

It happened 4 times and I had to MCEdit the map to fix.
The first 2 times I didn't checked about oil (first time I just deleted a whole chunk, it was when we started the map, and second time it was apparently just water flowing on lava) but the 2 other times the crash involved something interacting with some Oil BC: a Mining Well (from BC too) and a vanilla ladder or torch.

The problem is that there is absolutely no errors. Client freezes, and never closes so we must force quit it (which doesn't make any crash report). Logs don't show anything too. And server is fine, since only the player approaching the death point will freeze; other players on the server can keep playing.

At this point it's either a problem with Oil, or a problem with flowing liquid globally. This is why I ask here in case of someone had that problem with Oil too.

The map was made with World Painter, maybe that matters too?

We tried with and without Optifine, Shaders, Fastcraft (client and server), same results.

Edit: full modpack list: https://docs.google.com/spreadsheets/d/1KjeyC4Rm4ujiVXPadW6TaPjKpJmfuZEgiM0qywrtNcY/

Problem found, it was just Aquatweaks messing up the oil.