Since from what I understand, you are talking about the Dutch mod, so although I do not have explicit permission, I do have two things to my argument:
1. I'm trying to do a favor to the community.
2. I reasonably believe that there would be no problem.
And some more:
3. I'm not taking the idea as my own. I'll still credit Frozen- One for the idea.
4. If Frozen- One says I can't continue development of the mod, then I won't post it.
5. I have no bad intentions with the takeover.
6. If he ever goes on the forums again, he will find out and have a chance to tell me I can't continue development.
Sure, go ahead.
Thanks! I'll credit you for your part.