This may be a remain of the older Crash Bug which occured with Flashbangs, If none of the solutions I or anyone else posts work for you, Please contact Z8Games as they may need another update;
Z8Games - Support
1. Considering you just recently re-installed your drivers you may have downloaded an older version, Please try updating your .NET and DirectX And Graphic Cards;
https://www.mpgh.net/forum/243-crossf...esnt-work.html
2A. If Your computer or Crossfire seems to lag as stated above you may need to completely run a "Reduce Lag" spree on your computer, I suggest this tutorial for any leg reduction needs;
https://www.mpgh.net/forum/287-crossf...ucing-lag.html
2B. If you are experiencing problems in places other than just Crossfire, A corruption may have occurred when Reformatting, Please pay attention to any odd or malfunctioning situations.
3. When reformatting you may have lost some Crossfire Information, As stated above a Re-installation may help your problem, When re-installing be sure to do a completely and clean Re-install as shown in this tutorial;
[GAME ERRORS] GUIDE - Performing A Clean Installation Due To Errors - Z8Games