Hi
Thanks for your answer. here blelow the info requested.
Mac OS 10.14.16 (Mojave),
the DMG was not installed as the OS 10.14.6 is after 10.13 High sierra.
Nothing change after restarting the Mac
Moreover, I use VMware Fusion (11.5.7) for emulating a PC on the Mac and with a virtual machine running Win 7 x64, after installing lastest waveforms release, connecting AD2 works perfectly !! (so strange)
Thanks for your comments