I get the following error when loading the Audio Unit version of EWQL Symphonic Orchestra Play edition, and I can get no sound from it either:
"Build Routing Errors // Could not get channel info for effects (are they multichannel?)"
The VST version seems to work properly.
You can get a free starter edition here
http://www.soundsonline.com/free-orchestra
MacBook Pro 2.16GHz 2GB, Reaper v3.2, Play 1.2.5, Mac OS X 10.5.8