yes, you can use most HDRI images... a good place to down load some sky/sunset ones is evermotion.  Just remember where you saved them from, and in the assemble room click on Scene, then above where you clicked on scene you'll see different options, click on the arrows pointing down beside background and select HDRI, then browse for the HDRI you want to use, select it and you're on your way.

Hope this helps.

Christina -- "Love me but don't tell me so" Lilly Bart

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