I just uploaded some major changes to the CVS. Here is a list of some of the things you can do with the current code:
Create instruments with any number of inputs/outputs
Create patterns for the instruments and arrange them in sequences
Add some text to a document
Read/write instrument files that can be used directly in Csound
Read/write native Keso files, Csound files (orc/sco or csd) and mixed Keso/csd files that contain Keso-specific information in Csound comments so they can be played directly in Csound
Add user-defined ftables to a document (could be useful for samples)
Connect an output in an instrument to an input in another instrument
...and some other things. Of course, there's no UI yet, so if you want to do anything you will have to write C++ code.
Some plans for the next minor version releases:
0.2: Just the kernel (no UI, no non-standard C++ code). API documentation for all classes and functions. Almost there.
0.3: Basic GUI with a stable plugin framework and some simple plugins for editing the orchestra and creating/editing patterns and sequences. Shouldn't take too long once the kernel is done.
0.4: Advanced GUI with all those fantastic tools and features that I'm planning. A scripting plugin (I haven't decided which scripting language to use yet) for algorithmic composing and other fun things. An instrument library with generic instruments for subtractive synthesis, FM, sample playing and other synthesis methods, filters, reverbs, delays, distortion units and other effects. This might take a while.