DW 21.0, Build #15392 - Synced Custom Workspaces are NOT importing from the Cloud
Overall, importing synced settings from the cloud is kludgy at best. Sometimes it works, sometimes it doesn't. I had to perform the steps in the Preferences Panel 3 times before it worked. And custom workspaces never imported.
I submitted a bug report below:
My workaround on Win10 (v 2004) is to manually copy workspace files from old version to new version.
C:\Users [name] > AppData > Roaming > Adobe > Dreamweaver [old ver] > [language] > Configuration > Workspaces.

