I am having similar problems on my OSX box, with Miller's 38-3. Specifically with flext externals compiled from CVS myself, not from those I got from Thomas Grill.
I tried both pool and xsample and they both will not load, have not tried py yet.
hm ... i suppose, there are two different problems ... one flext problem and one pd problem ...
i'd love to get some feedback from matju on his problems with devel ..
cheers .. tim