Please, don't multipost. It's against the rules, if you want to change your post just click the modify button. ^^
I don't think you need to run anything to use Direct3d9. When you open Feralheart, a popup should come up. It will say OpenGL and a bunch of other options, just click on OpenGL and change it to Direct3d9.
If this doesn't work, try these:
Check your particles folder for any files ending in _0 or _1.
If you have installed object in the my_objects folder, I suggest deleting everything from that folder.
If nothing above works, reinstall Feralheart.
I hope this will help, floof. But I can't help with the virus thing..