I'm ASP.NET 2.0 YAF 1.9.3

I migrate all users, categories, forums, messages and attachments to yaf from other forum.

But if I push Moderate in main menu of Forum, I find category list, but in category I have no any forums.

But if I create category and forum after migration, in this category I can see forums and spam statistic.

Why can it be? If necessarry, I will post migration func.

Also can somebody tell me, how list of forums in category in Moderate Index control collects. I think, I forgot fill some data.