JDiskReport requires Java; get Java first, then download and install JDiskReport.

To work around the application quarantine in Mountain Lion, you can temporarily disable it, launch jDiskReport the first time, then reenable it. To change the quarantine settings:

1. Open System Preferences.

2. Click on "Security & Privacy"

3. Click the "Lock" icon and enter an admin user's password (usually your own).

4. In the "General" tab, find "Allow applications downloaded from:" and select "Anywhere".

5. Launch jDiskReport once. (This will add it to the system's "allowed" list even if you turn the quarantine back on.)

6. Back in the Security & Privacy system preferences, set "Allow applications downloaded from" back to its previous setting (usually "Mac App Store and identified developers").

You may also need to follow the additional steps below.

Before you can use it, you have to do some Modifications:

1. Download the app and drop it into Applications

2. Make sure Java is installed on Lion

3. Open the Applications folder, find JDiskReport and choose Show Package Contents (right click). Navigate to Contents/MacOS and delete JavaApplicationStub

4. Open a new Finderwindow and find JavaApplicationStub in /System/Library/Frameworks/JavaVM.framework/Versions/A/Resources/MacOS/JavaApplicationStub

5. Copy it into Contents/MacOS from Step 3. where you've deleted the older JavaApplicationStub before.

That's it