Beginner building - questions / complaints

[Krosis Priest]

So, I really like the game a lot and can forgive some things since it's EA, but I now reached the point where trying to build my first home the way I would like is very very frustrating for unclear reasons.

1. I previously made a new flame altar inside a cave I dug out myself, placed some basic items there (stash most importantly), moved everything from my initial home in the plains and extinguished that one. (Before that, both were marked on the map as HOME lvl 1, after extinguishing the initial one, the new one was still marked) After I reopened the game, my new home was completely gone. Please make clearer warnings and indications for this, as it seems I did everything as the game taught me and then about half hour of work + a bunch of items just vanished.

2. CANNOT BUILD HERE CANNOT BUILD HERE CANNOT BUILD HERE CANNOT BUILD HERE CANNOT BUILD HERE CANNOT BUILD HERE CANNOT BUILD HERE CANNOT BUILD HERE CANNOT BUILD HERE CANNOT BUILD HERE CANNOT BUILD HERE CANNOT BUILD HERE CANNOT BUILD HERE CANNOT BUILD HERE CANNOT BUILD HERE CANNOT BUILD HERE CANNOT BUILD HERE - why? There is no indicator or anything explaining what's blocking it. I could previously easily build inside a cave much like this one. https://steamcommunity.com/profiles/76561198016584584/screenshot/2540662890152960008/

3. Can the flame altar not be moved after being placed? It's a bit limiting, as it's required to have even a workbench.

Don't get me wrong, the game is great, but poorly explained things like these that can have serious consequences can really kill the fun.