I would say it doesn't hurt at all to do this. You can even open your forum to the public but not announce it for a couple of weeks while your working on content before your ready to share the forum's link.
I wouldn't go for it. I've seen it done on other forums in the past. It can cause bots to post spam or people who don't want to sign up and could make trouble on the forum just by posting as a guest. It's better to have the person sign up to the forum.
For a new forum I wouldn't have so many rules at the beginning. The obvious rules should be in place and either have a page to itself or make a sticky thread about it. When the forum grows and if need to can add more rules/guidelines to the forum.
I'd be pretty relaxed. As long as the members don't say hateful things about each other or show disrepect then I'll step in and handle it but if it's on topic and adds creativity to the discussion then it's okay.
It depends how many accounts you make. If it's one or two it shouldn't be too bad but anything more than that then it's a big no for me. As many have said people can easily spot it. I've spot it myself on forums in the past.
Yes I totally agree with this. For new forums I think they should spend their money on building content for the forum and then when it looks more active then you can start buying ads and things like that.
It's usually best to ignore them if they are just trying to cause trouble but if they have genuine concerns then its good to deal with it professionally. There will always be haters but unfortunately they might damage the reputation of the forum.
I only know English. I thought about learning other English but to me really there's no point as I don't travel that much and where I do travel they speak English pretty well. Once in awhile though if I talk to someone that knows another language I will ask them sometimes how they say certain...