Using another map on a bought module.

Hi! Been playing live for a while but because of the pandemic we changed to roll20 so here I am learning. I bought the maps for Dungeon of the mad mage mainly because I want the dynamic lightning, else I would've used some I found online BUT now that we are using them I'ld like to keep the dynamic lightning settings but change the background map with the ones I found online, is this possible? I tried duplicating the page but apparently it's doing nothing, it only creates a new page but no background image or dynamic lightning setup.

Duplicate Page is a confusing button.  What it duplicates are the settings for the page (size, dynamic light, grid, measurement scale, etc). A true page copy doesn't actually exist, but there are some hacks to get it done with a Pro Subscription (via Transmogriphier and/or API Scripts). That said, as long as your maps have the same layout and are just better textured versions, you can just drop them on the exiting map layer and scale them to the right size.  They will cover the current map, and you can swap between them by sending which ever is currently visible to the Back by right clicking and clicking "To Back".  If you decide you don't want to use them anymore, just delete the image and no harm/no foul.