Activity Monitor tweak on NBU 7.6

Hello guys,
I recently upgraded NBU from 7.5 to 7.6.
In the past I use with success this KB note:

How to manually adjust the number of days a backup job's history remains available in the Job Activity Monitor on Windows-based Master Server
TECH24317
http://www.symantec.com/docs/TECH24317

for adjust the numbers of jobs reported into Activity Monitor.
The same settings in the new environment didn't work:
do you know how apply the correct tuning?
Thank you for any tips.
Andrea