When λ is a partition, the specialized non-symmetric Macdonald polynomial E λ (x; q; 0) is symmetric and related to a modified Hall-Littlewood polynomial. We show that whenever all parts of the integer partition λ are multiples of n, the underlying set of fillings exhibit the cyclic sieving phenomenon (CSP) under an n-fold cyclic shift of the columns. The corresponding CSP polynomial is given by E λ (x; q; 0). In addition, we prove a refined cyclic sieving phenomenon where the content of the fillings is fixed. This refinement is closely related to an earlier result by B. Rhoades. We also introduce a skew version of E λ (x; q; 0). We show that these are symmetric and Schur positive via a variant of the Robinson-Schenstedt-Knuth correspondence and we also describe crystal raising and lowering operators for the underlying fillings. Moreover, we show that the skew specialized non-symmetric Macdonald polynomials are in some cases vertical-strip LLT polynomials. As a consequence, we get a combinatorial Schur expansion of a new family of LLT polynomials. 1.1. Main results. For an integer partition λ = (λ 1 ,. .. , λ), we let nλ denote the partition (nλ 1 ,. .. , nλ). We show that there is a natural action φ on the fillings COF(nλ, m) where each block of n consecutive columns is cyclically rotated one step. Consequently φ generates a C n-action on COF(nλ, m). In Theorem 3.2, we prove that for every n, m ∈ N + and integer partition λ, the triple (1)