Had a situation where my raider got the crit effect "you cannot resolve critical effects" and my first thought was my raider just got its flechettes effectively removed. But then I thought about it, and flechettes is a spend die ability, not a critical effect, correct? So I can still use the flechettes even with that crit on my ship?

It's not a crit effect.

It's a spend effect.

Plus you can't resolve crit vs squads anyway.

Oh yah that's a no-brainer there, I thought it worth bringing to the council though because I've been wrong on things I was sure I had right lol.