The term is "nol pros" is a shortened version of "nolle prosequi" - the full Latin term literally meaning "be unwilling to pursue" but more generally understoood as "do not prosecute."
Under Alabama law, the prosecutor is vested with full and unlimited authority to "nol pros" any case filed in that jurisdiction for any reason or for no stated reason. The prosecutor's decision to 'nol pros' cannot be questioned by the trial court; it is inherent in the executive authority vested in the office of the prosecutor.
The entry of a nolle prosequi as a disposition in a criminal case is, by itself, not an adjudication on the merits or a determination of the guilt or innocence of the accused. Therefore, in a technical sense, the case was dismissed without an adjudication on the merits. It is clearly not a conviction, but it is not an acquittal either.
Your best course of action is to take the renewal forms to a qualified criminal defense attorney in your area to assist you in completing the forms. The words "conviction" or "acquittal" or "disposition" have legal significance and it is clearly in your best interests to have a trained criminal defense attorney to assist you in this matter. For a listing of criminal defense attorneys in your area, check the listings for the Alabama Criminal Defense Lawyers Association at: www.acdla.org.