Kruszynski, Krusinski, Krasinski, Etc.: Variants of Surnames, or Differences?

The relevant surnames:

1) Krusinski/Kruszynski (Great-Granddad Czarnecki's paternal grandmother was the daughter of a Krusinski/Kruszynski)
2) Krasinski/Krosinski (I'm guessing that b. is a variant of 1a., though).
3) Krushinski/Krushinsky (Variant of 1b.?)

The "sh" shows those two variants to be Anglophone respellings.
You might have also added Krósiński and possibly even Krószyński. No-one spells their surname that way in Poland at this time though.

Krusiński is used by more than 800 people in Poland, Krusyzński by some 5,000.
Krasiński comes from a different root - krasa (beauty). The Kru- ones from kruszyć (to crush).

1) Good point, although I've not seen "Kroszynski".
2) So, "Krus" and "Krusz" are basically the same?

It's a spelling thing. In Polish the sz cannot precede -iński so it turns into -yński.
It's either Krusiński or Kruszyński.

Ah ok. Thank you for the clarification.

What about "Czokajło"? Is this a variant of "Czokało"?

CZOKA£O: from the now obsolete Old Polish verb czokać (to kiss, smooch, smack one's lips). Czokajło looks to be its Lithuanised version. The major concentration of both surname bearers is the Suwałki area of NE Poland along the Lithuanian border.

Thank you!