Pos.At(MaxArrayW-(10*CrystalSpawnNumber)*dt,0)
That should do the work ...
Pos is the name of the array
At() is the expression ...
-Manual
At(X, Y, Z)
Retrieve a value at a position in the array. Indices are zero-based. Reading values outside the array returns the number 0. If the Y or Z indices are not provided then 0 is used.
Cheers czar ...