I just installed this game, and I can't figure out how to get it to display in widescreen.

PC Gaming Wikik says to edit the .ini and change RenderMaxWidth and RenderMaxHeight, but I don't have those setting in the .ini

Have you tried adding those settings?

Yes, I have. The game still displays in letterbox. I've also used ResTool, but was given an warning when I start the game that the patch handles HD better.

I would just use ResTool, but the UI is off. Party display is not centered. It's located at the bottom left of the screen.