Rex graduated from NYU School of Arts in 1981 as a film majo - concentrating on writing, producing and directing. While there, he worked on several films and commercials, most notably Ms. 45 for director Abel Ferrara and Mother's Day and When Nature Calls for director Charles Kaufman. After graduation, Rex worked as 1st AD on dozens of commercials and films until he took a full time position at a NY Commercial Production Company.

In 1985, Rex became Head of Production for O'Quinn Productions where he produced numerous videos for Fangoria Magazine that were distributed by MPI and Paramount Home Video.

In 1987, Rex moved to Los Angeles where he was Head of Production for Associated Television International. Between 1987 and 1991, Rex wrote, produced and/or directed multiple TV specials and numerous travel videos. Piano also co-wrote and line produced the feature film Chill Factor starring Paul Williams, Patrick Macnee and Carrie Snogress.

Piano line-produced Severed Ties in 1991 for Fangoria Films and continued freelance production work until 1995 when he was hired to produce the syndicated TV Show High Tide starring singer Rick Springfield. Rex also produced two episodes that season, which led to him becoming on of the series rotating directors.

For the next several years Rex continued directing episodic TV shows, including Mike Hammer, Private Eye, Silk Stalkings, Born Free, Air America, and Nightman totaling over 40 episodes.

In 2000, Rex produced and directed the multi-awarding winning romantic comedy The Month of August. The film garnered nine Best Picture Awards and ten Official Designations at various film festivals around the country.

He followed that film with the highly viewed and critically acclaimed TV movie Hope Ranch for The Animal Planet channel. Rex then began directing TV movies that aired on PAX and Lifetime Television.

In 2007, Rex was the primary director on ROME - The Rise and Fall of an Empire, for the History Channel, directing seven of the 13 episodes that were filmed in Vilmius, Lithuania. Piano continues to produce and direct TV Shows and Independent films; the most recent being The Littlest Angel, an animated Christmas movie that comes out in 2011.