Im running SMF2.0RC2 to phpBB3.9, it goes through the conversion with no errors. Everything looks great, but I'm missing ~20,000 posts! I'm not even sure which are missing. It looks like the first posts made on the board are there, and the most recent ones definitely are there still. I'm getting no white screen or timeouts of any kind. It runs the full conversion till "success".
On my SMF install its shows:
Posts: 67591 Topics: 4599
Then when I convert to phpbb its:
Posts: 47517 Topics: 3105
If I go into phpMyAdmin it shows that the statistics are in fact correct.
If anyone can help me get this thing back to phpbb fully I'll gladly paypal you some money as a huge thank you! I've been trying to get back to phpbb for months and I feel likes its so close!

Also, if its any help this forum used to run phpbb around two years ago, then it was converted into a vanilla forum. I recently decided to move back as vanilla's production has all but halted. To do that I had to go Vanilla to SMF to phpbb.