am sure its a clash between your theme files and the menu in BP? Am assuming you are aware that in order to get BP up and running, you need to have a BP theme… its different from any other wordpress theme… this might help you out: https://codex.buddypress.org/theme-development/building-a-buddypress-child-theme/
Yes, the platform pro/pagelines theme is supposed to be compatible with BP.
I had the same issues you did. It looks like you got it to work. How did you do it, if I may ask?
MIne stopped working this morning after working for well over a year. Please help!