Dr. Andrew J. Marsh, the principal author behind Ecotect comments on a future Mac OS X compilation of the software in the Autodesk Ecotect discussion forum:

Basically I’d love to do a Mac version of ECOTECT…  I’ll need to go entirely OpenGL in v6.0 of ECOTECT. This will break the link with GDI and make both the graphics engine and calculation functions pretty well OS independant…  unfortunately it won’t happen in the short term, however its definitely in our future plans so…

Read the post on the squ1.com forum