If you are using the F-CF MOD 3.3 or 3.4 version, its normal that you will encounter CLIENT ERROR and HACK TOOL DETECTED, but it doesn't mean the the hack is not working anymore.
Here's some TIPS on how to avoid HACK TOOL DETECTED:
1. Activate F-CF MOD 3.3 or 3.4.
2. When you log-in in game and encounter HACK TOOL DETECTED it will aumatically close your crossfire client.
3. In your next log-in, do not activate the cheat anymore.
4. If you encounter hack tool detected again just don't stop logging in until you will not encounter HACK TOOL DETECTED.
For me I used to log-in for about 10 times before the HACK TOOL DETECTED stops.
5. Other TIP is try to log-in another account. If this account did not encounter HACK TOOL DETECTED, you can now lig-in your main account.
Here's some TIPS on how to avoid CLIENT ERROR:
1. Just use ctrl+1 ( 1HIT ), ctrl+4 ( NO RECOIL ).
Hope this will help!