Garmin downloader froze but downloaded file anyway

 

I'm trying to do the initial free map update for a Nuvi 285W I just bought. I downloaded the file using the Garmin downloader. The file made it OK (garmin_rmu_cnnant2010_40.dmg.dlm is on my mac with a size of 2.4GB). The download program froze however but strangely downloaded the entire file despite being frozen at 31%. I shut down the frozen downloader.

At this point, how do I get this file to my GPS given that I don't have the downloader running? I tried clicking on it and .dlm is not a recognized file type. Then I tried changing the extension to .dmg and clicking but my mac didn't like it. What I really need to be able to do is restart the Garmin Downloader but tell it that I have the file and want to install it.

Bill