Workaround:
1.- Open the affected scheduled task´s advanced properties.
2.- Check off "Show all possible attributes".
3.- Look for property edsaservertoexecute.
4.- Modify the value to: FFFFFFFF-FFFF-FFFF-FFFF-FFFFFFFFFFFF
NOTE: The number of F's for each section is: 8:4:4:4:12, for the above entry.
NOTE: The "Dynamic Group Checker" scheduled task is designed to run on only one specific server. Do not modify it in this fashion.
5.- Save it.
6.- The scheduled task now shows the "All servers" option:
Defect ID#: 297860 has been raised to fix this issue in a future version of Active Roles.