[Floppe]

Possible to get client frags exclusive targets bombed and hostages saved?

Need true K/D ratio calculated.

[ferret]

Doubt it. You could hook the messages for Bomb Defused and such though. Then you could keep count of the "objectives" frags and subtract them.

[Shaman]

You must make your own scoring system. Hook "player_death" event and count kills and deaths.
Also ONLY save the data (SQL or KeyValues file) when round ends. Saving data in "player_death" event causes lots of lag.