I've seen many trip reports on TPR to Holiday World. Some of them show Preimer looking trains and not the PTC we see today. When and why did they change?

Legend opened with a single Gerstlauler train in 2000. For 2002 they added a transfer track, and replaced that train with 2 PTC trains.

The reasons "I read about" included discomfort with the Gerstlauer lap bars, and the desire to standardize their wood coaster trains (with the PTC on Raven.

Interestingly, the station was somewhat different when it opened in 2000. The current loading area was a straight open air pre-ride section. The "dead space" in the the current station (behind a loading train) was the original loading area. This extension to the front gave them the ability to stop a second train while one is loading.

And, if what I've read is true, Legend's old train went to Geauga Lake to be used on Raging Wolf Bobs.

I don't know my Geauga Lake history at all, so will someone explain the timeline in which Legend's train was used? Was it in use during the derailment, or was it used as a replacement for the original (PTC?) trains after the derailment?

Raging Wolf Bobs never reopened after the derailment.

And the Legend train did run on the coaster:

http://rcdb.com/235.htm