Sept 2015 update 
http://www.ddlab.org/download/ddlab_compiled_2015/ and mirror sites
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There are 4 alternative compiled (.tar.gz) Mac OSX executables available, 32bit and 64bit

ddlabz03_macPowerBook32 OSX 10.4.11 (Motorola) PowerPC G4 PowerBook 32bit by Andy (andy at ddlab dot org)  
ddlabz03_macLeopard32 OSX 10.5.8 (Intel) iMac Leopard 32bit by Dave (noyzelab at gmail dot com)
ddlabz03_macMavericks32 OSX 10.9.4  (Intel) Mavericks 32bit by José-Manuel (jmgomezuam at gmail dot com)
ddlabz03_macYosemite64 OSX 10.10.5 (Intel) Yosemite 64bit by Genaro (genaro dot juarez dot martinez at gmail dot com)

These executables are probably incompatible -- use the one that matches your Mac.

Run DDLab from a terminal in X11, which must be installed.
From the directory with the DDLab files, 
enter the name of the executable preceded by ./ and followed by &, for example ...

./ddlabz03_macMavericks32 & 

Alternatively, first change directory to "ddfiles"
then enter the name of the executable preceded by ../ and followed by &
This will keep files generated by DDLab in the ddfiles subdirectory.

You can recompile DDLab yourself from the source code using 
Makefile_mac_z03, available at
http://www.ddlab.org/download/ddlab_code_2015/ and mirror sites.
DDLab would appreciate news of alternative compiles.
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