July 2016 update 
http://www.ddlab.org/download/ddlab_compiled_2016/ and mirror sites
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The following alternative compiled (.tar.gz) Mac OSX executables are available, either 32bit and 64bit

ddlabz04_macPowerBook32 OSX 10.4.11 (Motorola) PowerPC G4 PowerBook 32bit by Andy (andy at ddlab dot org)  
ddlabz04_macLeopard32 OSX 10.5.8 (Intel) iMac Leopard 32bit by Dave (noyzelab at gmail dot com)
ddlabz04_macTiger64 (Intel) OSX Mac 10.6.8 Tiger 64bit by José-Manuel (jmgomezuam at gmail dot com)
ddlabz04_macYosemite64 OSX 10.10.5 (Intel) Yosemite 64bit by Genaro (genaro dot juarez dot martinez at gmail dot com)
ddlabz04_macCapitan64 OSX 10.11.4 (Intel) Capitan 64bit by Genaro (genaro dot juarez dot martinez at gmail dot com)

Motorola and Intel are incompatible.
Use the executable that most closely matches your Mac.
32bit might run on 64bit but not vice-vera.

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 ...

./ddlabz04_macTiger64 & 

Alternatively, first change directory to "ddfiles"
then enter the name of the executable preceded by ../ and followed by &

../ddlabz04_macTiger64 &

This will keep files generated by DDLab in the ddfiles subdirectory.

You can recompile DDLab yourself from the source code using 
Makefile_mac_z03 
or 
Makefile_Mac_Yosemite_z04 for Yosemite
Makefile_Mac_Capitan_z04 for Capitan
available at
http://www.ddlab.org/download/ddlab_code_2016/ and mirror sites.
DDLab would appreciate news of alternative compiles.
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