I used to have a bad connection so what I did was take my laptop to where there was good internet and download there.
I used to do the offline updating but it's a bit clunky.
What you can do is simpley have CCC installed on the laptop, go updtae everything, then transfer all the downloads found in the command certer download folder over to your main DAW's same folder.
Run CCC on the mian DAW and it will use all those files to update without re downloading.
The Command center folder is found
Computer/ Program Data/Cakewalk/Command Center/Downloads