We tried the scrapers a bit, because right of peak some background appeared.

The GE01DS_HI shows a strange effect,
normal -65mm gives good resolution, -30mm kills the beam, but even more in at -15 there is beam again.
We suppose the scraper is not massive but has an empty space behind it.
GE01DS_HA has no effect even at +0V.
Therefore, put I to -100mm and also use GE01DS3HG (from outside),set to -55mm.
Then also the straight section EEXDS2HA from + 8mm to +10mm (a bit more closed).