Twixtor Plug-In Problems, please help

Hello,
Every time I apply Twixtor to one of my videos the computer locks up, it is very annoying because I’m editing a video for a friend. This is the setup I am using:
Display: Twixtored Output
Display Layer: All
Draw Geom: Checked
Time Remap: Speed
Speed %: 0.4
Frame: 0.00
Track Quality: Best
BG MotionSens: 94.74
Image Prep: None
cache OptFlow: Checked
Frame Interop: Blend
Warping: Forward
Smart Blend: Checked
Src:Mark Seg: Cut A
Any suggestions? If I were to fix this I could get back to editing again.
