Yes in horary we consider always antiscia-contrantiscia. As with the regular aspects, antiscial contacts can either show influence, or an event, in which case these aspects have to perfect, just like any bodily aspect.We don't move antiscia however. Regarding parallel i always keep an eye on them, but till now i haven't seen parallels given the same weight in horary as the major Ptolemaic aspects and I have not found parallels to be consistently useful in determining the outcome of horary questions as Ivy Goldstein-Jacobson mentions in her book