Comment 1 for bug 1558063

The reason is the game checks whether the warhead detonates over a bridge to then get either the "low" contents of a cell, or the "high" contents. This works for the bridges, but with higher CellSpread values, it also checks the "high" contents for cells that are no bridges, and thus there are no contents. It makes sense for smaller CellSpread values because the bottom of the bridge is far away in relation, but not for huge values, which would contain both levels.