WARNING: Dangerous build in triangle neighbor list.

Hi,
I have a problem one moth ago, and I tried to fix the problem, but is very difficult to understand.

I am trying to simulate the transport of grains in a single screw extrusion, for that i build two wall in STL format. One wall is rotating and another one does not move. I am using gran/herzt/history interaction and wall/gran/hertz/history for the wall and particles.

Firstly, I use particles of d=3mm, normally the message "WARNING: Dangerous build in triangle neighbor list." appears but the run does not stop, and the post-processing corresponds very well to the results expected.

But, when I use particles of d=2mm, the run stop.
I try to fix using:
-Decrease the time step from 1e-5 to 1-e6 for different values in the range, but doesn't work.
-Change the "neighbor 0.01 bin" to 0.1 bin, also for the run stopped.
-The particles are seeded in a hopper in the top of the screw, I changed the area of seeded but does not worked trying to keep the area from the wall.
-Now, I am testing changing the neigh_modify command to increase the page, one and check arguments, using this values:
neigh_modify delay 0 every 1 check no page 500000 one 5000
But I am not very positive with this strategy.

Also, I have a message from the exportation of STL file
"WARNING: Imported mesh contains skewed triangles with a size ratio larger 10"
This message is critical for the importation of STL files?

Somebody knows another strategy to allow finish the simulation?

Thanks!
Oliver