Hi iwicked,
Could you please try downloading the Dashlane application again for the site and run the installer again? It sounds like the Dashlane file that you first downloaded may be corrupt somehow.
(I can't post links apparently, since this is my first post on this forum. Sorry for that!)
Then download the installer there and run it. It will automatically download the whole application again and update your existing Dashlane file in your "Applications" folder.
If nothing still happens when you run the application, could you try and right-click on the Dashlane file in your "Applications" folder and select "Open" in the menu? Do you see anything then?
If you need, Dashlane's support can be reached on the site.
Hope this helps!
Xavier