Newbie developer... converting from VB6, some simple Qs.

Question

Please keep in mind, that I'm a neophyte here and trying to learn by doing. It's how I learned VB6 and pretty much everything else as well :)

I'm working on an application that has a few parts to it -- it will download files, display some news, and read some variables. I can manage to figure out how to download the files and display the news. My problem is that since the 'download' is supposed to happen in the background as a separate EXE (so that it can continue regardless of the main app being open or not), I wanted to know what way is proper to relate information back to the main app.

Let me explain a bit more... the main app is a 'launcher' -- it will download a little data itself and then (here's the hard part) pass that to the downloader. This would be say, a URL that is passed from one EXE to another. Now the downloader starts the download process -- showing a percentage complete, and passing that back to the main application. The downloader will be 'hidden' until the main form requests it to be shown.

How can I handle the interactions between two separate EXEs? Right now, I am planning on having two separate projects, one of which does the downloading and the other of which is the 'launcher'. If it's any help, if you play World of Warcraft -- it's a similar type of setup for their launcher/patcher though mine has a different purpose, the layout is the same for the EXEs.

Thanks for any help!
PS -- Doing this in VS2010 just so I'm learning the cutting edge and not the trailing edge stuff :)