Not knowing anything about who you're talking to about forum software, have you considered adopting Misago?
Riess is the creator of Misago, I would assume he'd be glad to have someone actually using it.
However I do not know the current state of development on it, if it's actually ready for someone to use should he be open to it.
Riess has been working on it for years now.
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PSA: If you have been having stutter/FPS lag on Disco where it does not run as smoothly as other games, please look at the fix here: https://discoverygc.com/forums/showthrea...pid2306502
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As said before, I have severe issues in using any kind of paid non open source forum software.
The reasons are plentiful:
1. Most likely a lack of any support (despite what forum devs might claim)
2. Security auditing is non existent in most of these small company type deals as opposed to well developed GPL based open source projects
3. We must pay to get security updates, insane
4. No mods of any kind because most likely license prohibits it
5. The features look nice but the amount of new problems created as outlined above is not worth switching to that particular forum software
Basically my stance on this is GPL or nothing. I remember being an admin on a vbulletin board and the amount of problems that we had with that, and how little support we got, how fixing problems ourselves caused more problems with updating. Any decent FOSS based forum is going to be miles better than any paid option simply because of greater community input, an emphasis on community modding and a greater support base. If we really need to switch, I propose SMF (http://www.simplemachines.org/).