Didn't work first time.
This is what I did:
1. Uninstalled 1.0.1
2. Deleted the cache and other files
3. Installed 1.0.2 (did not fix the problem)
4. Uninstalled 1.0.2
5. Installed 1.0.1 (problem went away)
6. Installed 1.0.2 (without removing 1.0.1)
7. Deleted the cache and other files
Now 1.0.2 works :-)
Strange and long winded. But at least it works.
For reference, in case it helps Webassist fix this problem: When the problem existed and I changed a colour the preview refreshed but the colours did not change. If I then clicked the preview to preview in a browser the colours had not changed in the browser either.