I’m a bit confused as to what the problem is exactly (?). It’s very hard to tell from a whole-brain projection onto a single slice whether the stray connections that you’re referring to are sensible or not (I assume this is showing all the streamlines with ‘crop to slab’ ticked off?). Some of the fibres you’re highlighting look like they could sensibly relate to anterior commissure, the other to the superior longitudinal fasciculus / arcuate fasciculus - neither of which are anywhere near the slice you’re showing. Likewise, the streamlines clearly cross the midline through the splenium of the corpus callosum, which is some distance above the slice you’re showing (currently it ‘looks’ like they’re crossing over the top of the brainstem). Those highlighted in your original post are harder to figure out, but again, it’s impossible to assess from a projection like this, these are 3D structures and there’s a good chance the streamlines still take sensible enough paths when looking at them at the appropriate anatomical slice location. They look like they do a U-turn in your single-slice projection, but that could easily be an artefact of the projection onto a 2D slice, rather than a genuine U-turn. I recommend you switch back to ‘crop to slab’ and follow these streamlines through the anatomy to verify whether they are sensible or not.
The other issue raised is that the fibres ‘look too winding’. I’m guessing this refers to their somewhat ‘wiggly’ nature? This is to be expected with probabilistic tractography: it’s designed to sample the range of possible connections, taking all sources of uncertainty into account. If you’re used to looking at the output of deterministic algorithms, this will of course look ‘messier’ than you’re used to, but in my opinion it’s much safer to obtain the full range of likely connections than just the most likely connection. In a probabilistic setting, you shouldn’t be looking at an individual streamline too closely, that’s a single random sample from the full distribution of possible streamlines. It’s the bulk of them that matters.
As to why you have a low count for the FFA, I can’t really answer that, I’ve no experience with this area and its connectivity. Do you expect to see homotopic projections between the contralateral FFA regions? I have to say, given where these ROIs seem to be located, this is not a projection I’ve noticed in the past… But others may be better placed to comment on this.