See this post for your answer. I had the same issue and resolved it with this. Just a couple of steps.
Amazing, Pairmybeer, a simple and elegant answer — it works — many thanks!
created a log in page as well using the same process
1) created a new page named “Log in”
2) added the following code in HTML:
3) added that page to my secondary menu
Still working on a layout for the forum homepage/landing page and having issues with some of the other short codes for forum and topic indexes
Thank you. For some reason, the page worked, but did not have the correct formatted look.
I just found that the bbpress widgets actually place the forum and the log-in in the right column, which may be even easier to use, and the page seems to be formatted correctly as well, so I will mainly use those.
The pairmybeer site looks good, and is very concisely branded.