You can use any version of firebird.
It just that out of the box local it will need ODS (On dis structure) for version 2.1
If it connect to a server the version can be 2.1 + but then the books cannot be put in books anymore without some technical changes.
Flame is just a way to get to your server data. what ever version you can use.
Have opened up port 3050 yet to test on the Network as we are down for maintenance I do have Firebird installed 2.1 w32 (I run a win64 also i note it is now at v3.0.5) should I install that version will osF still work
As for SQL etc going to have to get more reading on that one have no idea how I would even go about that
I as per the osF download have FlameRobin should I also upgrade to flamerobin-0.9.3.c75f861-setup-x64.exe?
I just want to make ure I do not Brick the program as I love it
Yes osf 5 offers single user network in the licence.
You would need to install Firebird on your server machine and make sure port 3050 is open.
Or if you go for the multiuser then you can access it with many users.
(Multi user also includes the osF 5 licence)
Then you could use tools like GBAK or if you convert your database to SQL server you can use the backup Scheulder from SQL Server.