The Preferences window can be opened by going to Extensions > Thea Render > Preferences.

General Tab

In the General tab you can change the plugin's language. Select one of the supported languages from the drop-down and restart SketchUp for the changes to take effect.
Autosave every (minutes): When Auto Save is enabled, Thea automatically saves the rendered image every 10 minutes (this is the default time, but you can change it). To find the Auto Save location, go to the Console of the Rendering Window.

Interactive Render Tab

Initial Appearance: Use the slider to find the best balance between rendering quality and responsiveness. The more responsive, the less precise the initial frame.
Resolution Reduction for IR Overlay: You can render at the same resolution as your monitor, but this is not practical when you have a high resolution monitor. The resolution reduction option lets you reduce the rendering resolution so you can render faster (the image still maps correctly to SketchUp view). It is highly recommended to use resolution reduction if you have a 4K+ monitor.

Channels Tab

Use the Channels preference panel to select a format. For EXR, you can select a bit depth for each channel. Note: Not all channels require 32-bit depth; only some (e.g., position, depth, and UV pass) will benefit from 32-bit depth. To save the render passes as one multi-layered EXR file, enable the option “Create multi-layered EXR including all channels”; otherwise, each channel will be saved as a separate file.