Database Transfer/Changes

**Hello. I have a large database from a PHPBB3 forum with around 20000 posts in that i want transfering to my new PHPBB******3** **database. The posts should: 1. Only include the FIRST post in every thread and include the subject 2. The post should be copied in the corresponding category 3. The post should be made to look like it was posted from a certain user id that i specify. 4. The post should have the next post id number. So what i need is: A query so that i can choose the forum i wish to take it from, and what i need to change to put it in new forum (changing the category id i guess) and that does the above. Please ensure you understand the above. All database information should be kept confidential but doesn't contain personal information. I look forward to your bids.** **