Help:VE270
From TrainzOnline
Density LOD multiplier in level <level> is not in descending order.
The density multipliers used across an asset's levels of detail must decrease as the levels get lower (less detailed). The named level specifies a density that is higher than a preceding level, or is negative, which is not valid.
Adjust the density multipliers so that each successive LOD level is lower than the one before it.
