- The Windows R GUI (RGUI.exe) could crash when typing beyond the bounds of the visible window.
- The “R” command wasn't available from the Terminal in OS X El Capitan.
- TCL/TK wasn't working on some Linux platforms.
- Using MKL on Windows 7 resulted in a “0xc000007b error”.
If you didn't experience any of these problems there's no need to upgrade, but if you did (or if you simply haven't installed MRO 3.2.3) yet, you can download MRO for Windows, Mac and Linux here. Note that to get the performance improvements, you'll need to download and update the MKL math libraries as well.