Well, I think I might be able to help you out, you see, SweetFX can be tricky to use. The one that installs with Crossfire 2.0 didn't work for me either, this is because I use Windows 8.1 x64 Enterprise, it will be like that for anyone using Windows 8 and above, SweetFX hates Windows 8 users. What I suggest is this:
Uninstall the SweetFX version installed with Crossfire 2.0. Download ReShade + SweetFX 2.0 here. This works with Windows 8 and with all my games, just make sure you select the correct Direct X level. Then head on to the creator of ENB and download this. (This is optional) it is a DX8 to DX9 converter for DirectX 9 effects.
The ReShade + SweetFX 2.0 you downloaded will unpack with a ReShadeSetup.exe file, which you need to run, select whichever game .exe from your computer you wish to enable these effects on, if the Auto-Detect function fails (Which it usually does) select the DirextX version the game in question uses; this can be gotten with a quick google search or checking the games requirements. In this case, it will be DirectX 8. If you can't launch the game with DirectX 8 while using SweetFX, then install the file you downloaded from enbdev.com. Take note; if you do this, you will have to re-run ReShade Setup and make sure you use the DirectX 9 installation instead, otherwise your game will crash on startup.
Enable the effects you want in the SweetFX_Settings file under the folder "SweetFX" this will depend on your taste, but with the settings I use, the game now look like this:
Before and After
Before and After
I hope this has helped you. 