I'm also having trouble with some aspects of getting FDR files working, but I think there's a problem with the file you provided. Each of the DATA lines should start with a Zulu time, and not have the "DATA" text. I'm not sure how picky X-Plane is about the format of the time: I use something like "20:25:27" and it works. [Reading your post again, perhaps I misunderstood. Does X-Plane accept the format you're providing?]
I'm using the PA-18, and it mostly works. But nothing I've tried will get the engine to run. It flies around as it should, but the prop remains stationary, there's no engine noise, and the tach stays at zero. I'm using the sim/cockpit2/engine/indicators/prop_speed_rsc[0], like in the example file, but it doesn't work.
