How does TileImage work?

No, that doesn't solve the problem. Sins I don't specify colour the dot's are drawn in white and the background is black so... I should be able to see them and I do see them but it's not tiled.

Here I've uploaded a screenshot of it: http://www.n-software.info/public/Game%20Development/BlitzMax/TileImage.tiff

Thanks anyway, Nicolas.