Strava Segments how-to

hi,

I'm new to Edge/Garmin system so please bear with me. Trying to figure out Strava segments on 540.

I've read a few old threads, and it's still confusing. I've read there's a limitation in how Garmin displays Strava segments (no downhill segments, or even flat ones? Why?).

Here's my situation (checking at home, WIFI, BT connection between 540/Connect):

1. I have paid Strava > 64 segments starred (same number on the phone app, as on Web).
2. Garmin Connect Web shows 64 segments (in some minuscule module on the Dashboard with links to Strava, why not a separate page on Connect?)
3. I make sure Strava segments are selected to use both on the Connect app and Web, as well as on the 540.
4. On 540, in Edit > Training > Live Strava Segments > 46 segments shown (I assume the rest could be flats and/or downhills) 
5. On the start screen scrolling Up to Segment Explore > nothing except the loading animation 

My expectations:

1. All Strava segments should show on 540/Connect
2. All segments should show on 540 when a route/course is selected or not, including uphills, flats, downhills
3. During a ride, segments should show up regardless if it's a route/course created on Strava, Garmin or whatever; if a segment is in 540/Connect, and I ride ONLY that segment, it should work

Am I missing something here on how to correctly set these segments? Are my expectations unrealistic? 

When are segments supposed to show up in Segments Explore: during a ride only, or anytime (like checking at home)? Or never?