You can switch MainStage between 32- and 64-bit mode following these steps:
- Quit MainStage if it is running.
- Navigate to, and select the MainStage application in the Applications folder.
- Choose Get Info from the Finder File menu.
- Enable the "Open in 32-bit mode" checkbox to run MainStage in 32-bit mode.
Disable the checkbox to run MainStage in 64-bit mode.
The following features are only available when you use MainStage in 32-bit mode:
- Recycle (REX) file support
- ReWire support
- Vienna Symphonic Library Tool
- AKAI format sample import
For more information about running MainStage in 64-bit mode, see the Logic Pro and MainStage 64-bit mode FAQ.