As far as I can tell it's _in_correct in every instance except the first:
À trois heures et demie = À trois heures et demie
Aller à deux heures et demie =\= 14 h 30 du soir [1]
A quatre heures et demie nous partons =\= À 14 h 30 [2]
A trois heures et demie nous allons au cinéma. =\= On va au cinéma à 14h30 [3]
[1] misses the "to go" part and also gets the time of day wrong- which is important because it uses 24-hour clock notation (and so it's obvious that it has no idea what 14h30 means).
[2] completely misses the action ("nous partons") and gets the time wrong ("quatre heures" is "four o'clock", not 14).
[3] Still gets the hour wrong (14h30 to "trois heures", i.e. three).
You'd certainly wouldn't want those translations to "help" you with your appointments in France, or Germany.
I was only referring to the time. "halb drei" is two thirty, which usually means 14:30 unless you specifically say "in the morning". The action in [2] would probably be added if you add a full stop.
[2] completely misses the action ("nous partons") and gets the time wrong ("quatre heures" is "four o'clock", not 14).
[3] Still gets the hour wrong (14h30 to "trois heures", i.e. three).
You'd certainly wouldn't want those translations to "help" you with your appointments in France, or Germany.