I converted a large forum a few months ago but did not have it optimized.
Matt walked me through all the issues, offered his suggestions and detailed the work as he worked on the server. Now the forums are supercharged so that speed is no longer an issue.
I imported Albums from vB 4.2 (took about an hour) and it worked without error and let me save an import log. However, even after rebuilding and checking permissions - no content in the Media section appears?!?