The cooling ith a tentative DRALS pattern works well. 
Cooling voltage in SC8 is now 905 V higher:
ESR manipulations -> Cooler maniuplations -> GECEBG1E is changed from +150V to +1055V. Please note the sign conventions. This means that the electrons are now 905V faster.
This is compensated by a DRALS pattern of -900 V (COOL) / 3300V (MEAS0/MEAS1). The -900V at the drifttubes decelerates the electrons.

The voltage is verified via the bunching pattern in the scope. The bunching signals look best in a flattop of about +1050V to 1060V. 1050V is the design value (1050V -900V = 150V).