Read you PM/Conversation for information about how to find (Audifon audifit5 and audifit4)
As to (Helix helifit) please read the reply to your previous request → Helix Direct link download on this same subject;
As to (Sound tech Software) my answer is the same as Helix. I don't know about (or care about) OTC (Over The Counter/Cheap Retail) hearing aid software.