Brickdoh v0.53 has only some code cleanups and one minor feature added, compared to v0.52 - bricks have now a "flip away" animation when they break.
To run Brickdoh, just download the brickdoh.jar. If you have Java 6 properly installed, a double click on the jar file should start Brickdoh. If this doesn't work, please check the project Wiki for instructions how to start:
The brickdoh-trunk.tar.gz archive contains the sources, images and sounds for this release.