Etrex 20 Mac-newbie basecamp quesion

Just got my etrex20 so not even sure what questions to ask much less the answers. After countless hours & googling now understand some of basics. 1st question: I’m using Basecamp & also have maps on Sandisk micro 16gb class 10 card. Have already downloaded Florida topo & Florida openfietsmaplite to get streets. Seems to be working but when downloading maps do I install 1 map in Basecamp “ = Installer for Garmin BaseCamp/RoadTrip (Mac OSX)” & second map “ = Combined image for direct manual placement on the GPS device (gmapsupp.img)” to put directly on SD card? Or once map on SD card will Basecamp be able to import it directly from SD card? Thanks for any & all help. Will definitely be DONATING as soon as I have much better handle on this device. By the way … any users in Tampa Area of Florida?

Yes, BaseCamp can read the maps from a memory card on a device. Though this will only work when the device is plugged in, and may be rather slow.
So its usually better to install the maps on the computer as well.

You could download the maps and install them in BaseCamp, then use BaseCamp to load them onto the Etrex. Though it may be quicker/easier just to download the separate gmapsupp.img version, and just put that on the memory card.