20130101

- Make use of runningUnder() to avoid lwsn crashes.
- Tweaked hard-coded, obsolete, reference to ScreamerNet.
- First run under OS X!
- Bumped minimum requirement to LW 11.0.
- Further tweaks to refine operation.
- Moved Motion Mixer handling to a separate function to reduce
complexity.
- Moved buffer handling code to a separate function to reduce
complexity.
- Modified writeOverrideString function to handle 'special' case of
FrameSize and GlobalFrameSize settings.
- Deployed improved scene file writing code. Probably broken build for
now. Will debug over time :)
- NT helped with guidance to avoid the arithmetic error on OS X. It's
that this_script[1] in the main file (and also in the interface
subfuncs file).
 - Reworked this code per NT's guidance.
 - Have followed up the reply with a query about why the error location
is always wrong.