Bus schedules/service info for Orange, Nimes ...?

I see that there is note on the tariffs page of the Edgard website that mentions, if I'm reading it correctly, a one-day pass that admits one to the Pont du Gard attractions and also allows all-day use of a number of lines, but I can't puzzle out which lines go where when, and how to find it in Nimes:

Tickets combinés Edgard + Pont du Gard
Entrée sur le site du Pont du Gard + libre circulation sur les lignes A15,B21,E51 et E52 pendant 1 journée.
Famille --------------------------------------------------------- 20 €
Valable pour 3 ou 5 personnes dont un adulte.
Individuel --------------------------------------------------------- 10 €
Valable pour 1 personne.

Anyone have English listings for these bus routes? the B21 seems to have a stop at the Uzes museum, so maybe that's what I need?

Unfortunately bus operators in France rarely have an English website. Useful words to look for are "plan du reseau" (network map), "titres" or "tarifs" (fares) and "horaires" (timetables). It's also a good idea to check out the French days of the week, as it's common for a timetable not to have separate timetables for Saturdays or Sundays, but to show abbreviations for what days journeys operate in the column header.

If you're searching for bus operators, the best thing to put into a search engine is the town name plus "transport en commun". If you're looking for anything smaller than a large town, the best thing to do is to find out the name of the departement that the place is in, and search that name with "transport en commun".

Specific links for you:
Orange town bus services: http://www.sudest-mobilites.fr/informations_reseaux.php?IDReseaux=6
Vaucluse departement bus services: http://www.vaucluse.fr/2826-lignes-et-horaires-du-reseau-transvaucluse.htm

Nimes town bus services: http://www.tangobus.fr/
Gard departement bus services: https://www.edgard-transport.fr/

Nice and surrounding area bus services (includes Vence and La Turbie): http://www.lignesdazur.com/

Be warned that the only one of these I've personally used, the buses between Nice and Vence, can get extremely crowded at weekends and during the tourist season.

Specifically from the Edgard website, the ticket for the Pont du Gard is described at https://www.edgard-transport.fr/presentation/?rub_code=54. If you click on the link towards the bottom of the page which lists the bus routes serving the Pont, it will take you to a page that links to timetables of all the Edgard routes in number order.

In addition to getting schedules online in advance, we recommend to re-confirm your next travel plans upon arrival in town at the train/bus station (or Tourist Info Office), especially if there are only 3/day. In Nimes, trains and buses use the same station.

Since the Nice bus station has been demolished, you just go to the stops. Read a little deeper in Rick's transport summaries at both the start and end of each chapter; for instance www.lignesdasur.com is mentioned on p. 336, toward the start of the Nice chapter. Those coastal buses run frequently.