I am having this problem, also. Using Version 2009 (279), Everything Pak, as shipped on external HD. Not only LOADING the song, but every time I change anything about the arrangement (i.e., add an extra measure). BIAB goes through the entire song, bar by bar, generating a yellow or blue error pop-ups. For 49 measures, this took just under 7 minutes for me. (Bonus question -- is there a way to abort this process? It just hangs up the entire program till it's finished. Sooo frustrating!)

For what it's worth, the folder is Rhythm Syncopated Sugar Ev 102, all wma and bt0 have same date and name, and are matched in number.

Thanks in advance