A few counterpoint questions if y'all don't mind!

[bofonic]

Hi I had a few questions on 16th century counterpoint and having no idea which forum this might go in I decided to use this one:)

So without adieu! I'm currently working out of the Fux/Jeppeson combination and had a few questions to those experts how there.

1) As far as treating any intervals dealing with F and B is it better to avoid them altogether? Or is it OKAY to change the B into a Bb and F into an F# when writing out the counterpoint?

2) How strictly should I follow Fux's requirements of intervals before the final cadence? i.e species 1...3 for top CF and 6 for bottom CF and species 2 following those with 5?

3) Is crossing voices okay? How the heck does it work? I've been treating most of my counterpoint/cantus firmus as soprano/alto respectively switching the CF from top to bottom.

4) Are ascending leaps permissable from the Third beat to the fourth beat in 4 quarter notes against the whole note (Species 3.)

That's all for now I think:) Any help would be appreciated thanks!

[faulty_damper]

1. the tritone can be used as long as it resolves.  I.e. B-F > C-E
2. it's music, not theory.  Do what sounds right.
3. Yes, it's fine to cross. Pedal point the soprano while the alto flourishes above it.  Other techniques work as well.
4. Yes, ascending leaps can work, though it's best to resolve down a step, ideally a consonant resolution.

[chopin2015]

Uhm, dissonance is good as long as it is "allowed", species 2 and later. Also, modal counterpoint and tonal counterpoint have different types of cadences and beginnings.

In modal counterpoint, the f to b and b to f should be used in keys like G major/E minor (b to f being a perfect 5th) or F major/d minor (f to b). Also, I believe that CF and CP are invertible in modal counterpoint, unlike more tonal settings.

3) I like crossing voices. Also, I like transposing the phrase that contains the dominant scale degree-up a 5th.

4)as long as the 3rd beat is not a dissonance (it shouldn't be, as it is a downbeat), and the 4th beat can't be-either. You cannot leap from a dissonance, to a dissonance, or across the barline.