Recently a question about Dynamips/GNS3 configuration popped up. Is this a relevant question for the NE site?
If Lab software is part of the Network Engineering landscape, then absolutely these questions should be on topic here. As a matter of fact, the developers of these applications tend to have communities of their own, and these special interest groups have become a huge source of excellent questions and avid, supporting communities on a lot of sites. If these questions are being asked, we should encourage them to become part of the ecosystem of this site.
This is really no different than what we've done on Stack Overflow (and a lot of other sites) for quite awhile. Check out the top two answer in this thread for details.
We get a lot of requests from project teams about how they can use Stack Exchange to support their communities. I see no reason why this site couldn't provide fantastic technical support for end-user products used by network engineers! This doesn't mean that companies should outsource their entire customer support channel here (e.g. no bug reports, feature requests, etc). Network Engineering SE should be but one support option for these products — community-driven technical support.