I've been following the docs on the GitHub wiki (https://github.com/liballeg/allegro_wiki/wiki/Allegro-Vivace%3A-Graphics)
and I keep having an issue where multiple windows open before the main window opens

show code please? At least the initialization portion.

This seems to be (on Windows at least) directly related to:

al_set_new_display_option(ALLEGRO_SAMPLES, 8, ALLEGRO_SUGGEST);

Comment out that line and it will stop.

This is in the middle of being fixed. Please stand by.