ABout backups when using servers
On the Z site it says it's very important to backup often if you use one databse on svereal computers, like storing databse and the sqlite file in Dropbox. And it is true that if you are not careful you might end up with an older version as the main version. BUT it looks like Z makes those bakups itself? I had this problem and just remade a sqlite.BAK and all was OK. SO about the warnings am I missing something here?
The numbered backups you see in the data directory, by the way, are different: those are made when Zotero upgrades the database and (at the moment) are likely to be many months old.