I'm running BIAB from an external drive and I'm having a strange problem with the BIAB DAW plugin I'm using with Logic Pro: 

1) I create a song in BIAB, complete with various RealTracks, which all appear in the mixer panel of BIAB.
 
2) I save the file and then launch Logic Pro.

3) I open the BIAB DAW plugin and try to load the same file I just saved in BIAB into the plugin.

4) It then loads and says it's generating the file. But when it's done, the style I used in BIAB is not there. Also missing are some of the real tracks.

I'm not sure if this is related, but when I do a re-indexing in the BIAB style picker, it says I have 7592 styles, but when I do a re-indexing from within the DAW plugin using the style picker it says I only have 5002 styles. 

Any explanation for this?

Thanks.

In the Plugin Preferences set the Folders to the same hard drive & folders Biab is using.

there is a bug that won't allow me to see the real track or drums on an external drive without rebuild the databases

The above suggestions are both great. We'd just would like to give a bit more detail to make it clearer for the steps to troubleshoot.

In the Band-in-a-Box plugin, please go to File | Preferences and scroll down to the folder paths for your Band-in-a-Box, RealTracks, and Drums. Are these paths correct? If not, please click the "select" button for each to search and select the correct folders. Your RealTracks should be in the RealTracks folder and your RealDrums should be in the Drums folder. Afterwards open the Style Picker inside your plugin and click the Rebuild button. Your tracks should be found after these steps.

A Rebuild should be done after changing any folders, or after any new installation, whether it be a build update or installing new RealTracks.

Je ne sais pas reconstruire après cette étape qui pourrais me montrer?

Google translation:

I'm using the Band-in-a-Box v3.4.6 Standalone Plugin for the screenshot.
Select > Realtrack ... > Rebuild

Google translation: