Hi folks,
I don't know which specific step solved the issue for me, but this is what I did:
Installed BandLab as administrator;
Clicked "Install" without selecting any add-ons;
Once the 500+ Mb exe file was fully downloaded, I executed it explicitly as administrator (it didn't automatically install);
After making sure CakeWalk was able to start, I went back to BandLab Installer and installed all 4 add-ons; this time the installation was automatic - and sequential, one after the other - without me having to explicitly execute the 4 exe files.
I hope this will help some. Cheers!
Chris.