I had the same problem. While watching the program run, I noticed that after it indexed the folder where my PHPBB files are located, it kept running through the list of all the remaining pages in other folders, but wouldn't index any of them. I then added the PHPBB folder to the do not index list, ran again, and it went from 982 pages to 6038 pages, which is about right.
The strange thing is that it still appeared to be indexing the PHPBB files. I would prefer to understand what what hapening, but with my busy schedule, I'll settle to just having it work anyway it takes.
BTW, it didn't matter whether or not including the pictures was selected when I was having indexing problems. It is definitely nice to have the images indexed now!
- Kirt Blattenberger