There is currently a Kickstarter campaign underway to develop BRPG v2, which will actually be called Battlegrounds Ultimate (BGU). One of it's goals is to restore full support for Mac OS. A Stretch Goal would add a "free play" mode, where a license would not be required to use the software in actual game sessions (although the featureset would be somewhat pared down). There is even the possibility of offering the user interface in other languages, such as German, French, and Spanish. Please consider supporting this project.
Battlegrounds Ultimate