The trial version of MC12 is fully functional. It is only time limited, not crippled.
The Apple Lossless format (ALAC) is not open and MC12 must use external software for decoding it. (BTW, Apple Losless is not an AAC codec. It is a completely different format. Apple uses the MP4 container file format with the m4a filename extension for both encoding formats.)
If you have installed Apple's QuickTime, MC12 uses it for decoding m4a/ALAC. Some important features like Replay Gain, Internal volume, DSP, file converter and visualizations are not available with QT decoding.
It is also possible to install
DSP-Worx ALAC DirectShow filter. If the DirectShow chain is properly configured it should be able to decode ALAC files (it works for me with FDDShow & Haali splitter). This makes possible to use many of the features that are not available with QT. More info about configuring DirectShow is available here:
http://wiki.jrmediacenter.com/index.php/DirectShow_Playback_Guide