the autofocuser based on HFR will not be affected by this and stay the default option.
In fact it would be possible to use the offset calculated by the Bahtinov fitter to drive the autofocuser.
In a fully automatic setup this could be combined with a mechanics that places the mask onto the scope (similar to what some people have for flatfield caps). But we are digressing.

For the streaming mode we have to see. The fitter works on the image frames, so in principle it can be done. The question is performance, i.e. at which framerate can we produce the solutions. It definitely will work in a frameing mode.

Short status report: the algorithm that extracts the diffraction pattern and fits the Bahtinov lines to it, thereby measuring the offset of the center line is implemented in my local copy of EKOS.
Since I had to switch to GSL for the numerical libraries, I am working some convergence issues. Next will be work on the graphics (plotting the lines corresponding to the found solution).

I'll post pictures as soon as I have something presentable.

Cheers, Sebastian