- I had the same issue;

- solved:

1. drag the image file on your desktop

2. double-klick on it;

3. a installer window will appear;

4. do not double-klick on it, drag the "WMware Fusion"-App in your Program-Folder;

5. you will be asked for your credentials;

6. now double-klick on the VMware-Fusion-Icon in your Program-Folder and it will install it without problem.