Hi Austin,
Yes, it is intended that table-to-table imports do not work in a sandbox. The reason is that table-to-table imports automatically bring all of the related applications involved into a thread that shares the same computing power, and creates a situation that is ripe for crashing your app.
That being said, you can copy all of your live data directly into your sandbox when you create the sandbox (just select "all records" in create dialog). The record IDs are maintained, and it's as if you're looking at your live data.
Does that meet your needs?
Best,
Chris
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Chris Hutchens
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