So, after consulting with GRAPHISOFT, here is the answer:
Yes, using posts to promote one's products or service is contrary to the Forum rules. Normally we move such posts to the Ads forum. However, if the post is about some free and useful content that is beneficial for the ARCHICAD-Talk community, (not a promotion of a product or service), that is OK.
Yes, it is allowed to use links in your Signature that point to your web site or a product or a service you are offering. However, it all has to be ARCHICAD-related since this is an ARCHICAD-forum. We usually ban any user that places non-ARCHICAD-related promotional links into their posts or their signature (especially if they have no posts since those are surely spammers).
Also, we prefer users promoting themselves in Signatures only after they have shown that they have contributed to the ARCHICAD-Talk community. We feel users with 100 posts or more have demonstrated this. (So Anton could also do this in his signature as he has more than 100 posts.)
GRAPHISOFT feel this is something contributors to ARCHICAD-Talk deserve. The Signature's length is limited, so it is not possible to create very large signatures full of promo stuff and links.
We will update the Etiquette page of the Forum so there is a written reference anyone can turn to if there is any question about this topic.
I hope this clarifies things. If anyone has any other questions, please ask.
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