As far as the negative value problem, I found you can type the value in notepad then copy and paste into LfsTweak. Kind of a pain but it works.

Got me home when the clutch broke and wouldn't disengage in my 83 Celica. Started it in gear then syncro shifted all the way home.

I have much better luck catching slides with my DFP if I only use 270 degrees instead of the full 900.

I've used them for pc based flight simulators. Words don't do it justice. What it does for depth perception is just amazing. I've used both the small ones and one I took from a big screen tv with my projector shining on it. It also is really cool if you hold it under the sun, melted a hole into the pavement with the big screen lens.

Did you try the wheels only view with the wheels turned off? I believe its under options, one of the custom views.

Many race cars in real life don't even have speedometers. What ever line gives you the highest engine speed at the end of the following straight is what I had always been told was the fastest. Split time also will tell you a whole lot.

Revving an engine without a load on it, especially full throttle to redline or beyond is very hard on it. Even with a limiter I would still think it would be pretty bad for it.