Load .amf Files

I'm trying to load .amf files into Slic3r on my Mac (Sierra 10.12.2) for use with my new Geeetech M301 3 extruder printer. Slic3r 1.2.9 gives an error "Unknown option filament_settings_id" which varies according to my settings but I can't figure out how to get rid of it.

I also have a version 1.30.25RC1.3 (don't remember where I got it) which gives an error "AMF parsing requires XML:AX" when trying to load the file.

I have tried to compile a later development version according to the instructions on the Slic3r GitHub page but it fails with build errors due to 10.12 not being supported.

Any recommendations? Does anyone have a later precompiled version compatible with Mac OS Sierra? Any idea when a version newer that 1.2.9 will be released?

Thanks!

--Dave