So, I almost only get to see Ice Lance in the main icon. Even when it's a single target, it is not frozen etc. Almost never seeing frostbolts or anything else...

Spec: 2312121

I'm unable to replicate this issue. The rotation works as expected for me.

The line you're referencing requires the Winter's Chill debuff to be active on the target, so I highly doubt that it would somehow hang the rotation on that line.

Here, the condition seem to be erronous:
if S.IceLance:IsCastable() and (Target:DebuffUp(S.WintersChillDebuff) and Target:DebuffStack(S.WintersChillDebuff) > num(Player:BuffUp(S.FingersofFrostBuff)) and Target:DebuffRemains(S.WintersChillDebuff) > S.IceLance:TravelTime()) then if Cast(S.IceLance, nil, nil, not Target:IsSpellInRange(S.IceLance)) then return "ice_lance single 18"; end end

Specifically, Target:DebuffStack(S.WintersChillDebuff) > num(Player:BuffUp(S.FingersofFrostBuff)) If num(Player:BuffUp(S.FingersofFrostBuff)) is always 0 it will always be suggested to get cast.

Here following the rotation I had to press ice lance until mob was dead.

Changing to Target:DebuffStack(S.WintersChillDebuff) > 3 unlocks the rotation, but obviously this is not a fix