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Egg, I made it very obvious on purpose to show how to create a seamless set of boxes. What you do with the method is up to you.

Acorn

Egg's demo is useful but @shipen might not realise how to take anything and make it seamless.

130703

The larger, lower block is a rectangle with the letter B, clone and flipped to the right and...

shipen, Xara provides a very limited range indeed.
All these fill are just jpegs that have a seamless texture.

Just try a Search: brushed aluminium steel seamless texture fill.
I am sure you'll...