I was having the same problem, and after two days of troubleshooting and doing everything I could think of I finally decided to put the "outside sandbox" marker inside the home. So there's one marker outside and inside the home, and it works just fine now.
The problem for me was that all the doors of my home where in a pre-existing location that would not recognize any new markers I added. Even when I created a new location and attached it making the pre-existing location the parent, the script still wouldn't read any of my new markers.
I hope this helps!
Cheers.
i confirm this works too, did a lot of homes and they worked just fine, but lately the no outside sandbox error started poping out, and putting one sandboxOutside marker on the inside fixed it, for some reason, the only thing i didnt manage to fix yet, is the No linked bed one
Make Your Home Multiple Adoption Friendly
in Skyrim LE
Posted
i confirm this works too, did a lot of homes and they worked just fine, but lately the no outside sandbox error started poping out, and putting one sandboxOutside marker on the inside fixed it, for some reason, the only thing i didnt manage to fix yet, is the No linked bed one