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Again, this works for Buttons, Tab bars, Lists & Swipes:
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Buttons
At the Properties tab (marked green ↓) select the Icon Class (marked red ↓) and just PASTE your buffer from Step 1 into it.
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You will see your icon name appear in Properties and the icon itself on the screen.
Tab Bars and Lists
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Swipes
At the Properties tab click needed element of the Tab or List, marked Red ↓:
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