I too had problems 4-5-6, I just kept my height 4 to 5 expecting to be at the top of the slope but had to drop down to even find the slope. (Contours seem to vanish between the two on my map).
Again 5 to 6 should have just involved contouring but I also found myself facing a large unmapped spur but eventually spotted the control at least 10m above me. The vegetation may have helped to locate the controls but it all looks the same colour to me.
Glad it wasn't just me. What you've described was exactly what happened to me. The old map shows this area far better with the spurs having much more clarity / prominence. I think it's these new Lidar-based maps where the contours produced seem to be taken for granted (they may be technically correct?) and not manually adjusted to show what an orienteer sees.
The vegetation wasn't much help. Again it was probably correct when seen from above but when you're on the ground trying to run through the terrain the map colours weren't much use.