Regarding Linux & Mac:

The new cpuminer version that is coming out in 7 days is almost completely cross platform with native Linux/Mac compatibility.  Im working hard to remove windows features and make the new versions cross compilable.

In the mean time, you can download the windows MSI and run it on Linux in wine with "wine gridcoin.msi", after it installs, run the shortcut, and you should be able to mine with that version.

Rob