Hi Mihai,
I’m really sorry, but I don’t give support for sphinx or acoustic model adaptation or generation here; I have to stick to the given scope of offering support for the OpenEars API.
Your initial issue could be sphinx version related, but as a heads-up, there will probably be a secondary issue, in that OpenEars’ acoustic model bundle format is custom to Politepix, so it is not necessarily the case that your sphinx adaptation results will be OpenEars-compatible, and that is going to unfortunately be outside the scope of the support I give here to troubleshoot. I wish you the best of success with this advanced topic in local recognition.