BPP does give the user control over a small subset of the StarAlignment parameters (interpolation mode, clamping threshold, max stars, noise reduction and whether or not to use triangle similarity.) i am not sure if the rest of the StarAlignment parameters are left at default or if BPP overrides the defaults behind the scenes. i'd have to read the source code for BPP and then compare any other settings BPP changes to see if they are the same as the StarAlignment defaults.
at any rate what is the error message in the console when you try to use BPP to register your frames?
rob