I have been trying to simulate one of my project in Mike+ with 2D overland flow and few coupled nodes. I have had created Mesh from Mike+ and it looked good for me, but when I simulate the project with higher order (accurate algorithm) it always gives error of blow up elevation too large. I tried to alter the mesh but still it didn't work. even i have tried to change / lower the timestep but still it gives same error.
then i tried to simulate it with lower order (fast algorithm) and it simulates without error. 
I want to understand how good are results from lower order solution compared to Higher order.

Also what can be possible solution to avoid blow up elevation too large error in order to make the model simulate with higher order?