it will be a part of 3.0 (builds 85x or higher). Each DMX channel in QuickDMX tab has option "Sub master". By means of this option you link the channel to one of 10 sub masters. After that, you can control sum master as object:
DmxMasters[1].Value = 50 // 50 percents
Also, there is
Master.DmxMaster
This is main master.
Best Regards,
Alexey