I bought mine in the Vintage Instruments package and there was a "spare" CD in there which had an update for the miniMg on it, although it took a little digging around to find it. I imagine you'd have installed that if you had it but, just in case, I installed and launched it, found that it didn't work, then found out that it (the update) had to be launched with the original miniMg program disc in the CD drive (phew!) and then it worked. (Thirsty on the CPU, mind you).
Having done that, I now have the standalone and the AU version working. I'm afraid I can't mail you it because I've got a very slow dial-up connection and it's 40 MB.
On the off-chance that you did get an updates disc, you have to click on the HTML "Mac index" (or something like that) file and open Safari and take it from there.
I suspect you've done as much as you can for the time being though - I feel your pain but all I can say is - the update does work and I was in just the same situation as you before I installed it.
Oh - and also I found a message in a google cache of an Arturia page (currently unavailable due to the Arturia site being down). It basically apologised for the support being a bit useless just at the moment, because of holidays, and said that the worst bit would be August 26th until September 4th. So hopefully they should be getting busy again tomorrow and getting the site back up. So with luck you won't have to wait too long.
Good luck.
Cheerio.