Archicad 9 must be 12 or 13 years old now and I doubt it is being supported by any 3rd party add-on developers any more.
Archistair was a Cigraph product, so you will be best to contact them if they are still around.
They do still have a website although there seems to be nothing new since last year.
http://www.cigraph.it/en
And their support e-mail is...
support@cigraph.com
Barry.
One of the forum moderators.
Versions 6.5 to 27
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