Nicole Curtis‘ ex Shane Maguire is dragging the former HGTV star to court to try to change their custody arrangement … months after she was fired from the network for using the n-word.

In court docs, obtained by TMZ, Shane asks the court to modify the current custody plan from one that involves frequent exchanges to one that allows their 10-year-old son, Harper, to have one week with him followed by one week with Nicole.

Shane claimed the current custody arrangement is creating “conflict” and “instability” for Harper and exposing him to “ongoing parental conflict.”

In his paperwork, Shane says he moved from Michigan to California after Nicole claimed she needed to be there for work. But he says that “ultimately did not prove to be accurate” because Nicole still has to travels often for work.

In his filing, Shane says he continues to have problems with Nicole, particularly surrounding custody exchanges and communication.

He says Nicole has “demonstrated a pattern of creating conflict during [custody exchanges], even in situations where there is no underlying issue and they are often contentious.”

Nicole’s ex claims there have been “multiple occasions where exchanges at or around school have escalated into conflict, with [Nicole] creating tension or scenes in Harper’s presence.”

He says he was volunteering when Nicole appeared and created tension, “turning what should be a positive interaction into an uncomfortable situation.”

Shane says he believes a change in custody schedule would benefit their son … and he wants the court to change the custody schedule to support his emotional well-being with better structure and stability.