Hi @gnozo.
To get rid of those warnings, remove /Users/gnozognozo/Library/Application Support/SuperCollider/Extensions/__MACOSX/. This is a spurious folder that was included in sc3plugins in error (MACOSX folder in release zip · Issue #279 · supercollider/sc3-plugins · GitHub).
exception in GraphDef_Recv: exceeded number of interconnect buffers. is probably important, see Linux install script fails - #9 by yaxu for a solution to that (despite the title, the advice applies to macs as well as linux).