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The remaining parameters control how the texture is scaled and translated in texture-space. Tile X & Y can be enabled or disabled using the appropriate checkboxes, and their values are set using the numeric input box. When Real Scale is not enabled (Units box set to Relative), the meaning of Tile X & Y is roughly, ‘squeeze this "squeeze these many copies of the texture into the given space’space". When Real Scale is enabled (Units box set to Meters), the meaning becomes, ‘make "make each tile x-number of meters wide’wide".
The Channel parameter allows you to associate different textures with the different texture-projections which may have been defined for the objects to which this texture is assigned. For example, some textures may use a cubic projector on channel 0, and a planar projection on channel 1. Each texture mapping, channel 1 & channel 2, represents a different set of UV coordinates. Setting the Channel parameter in each texture individually allows each texture to use whichever mapping is appropriate. If an object has fewer texture-mappings assigned than are specified in the various textures its material has, then copies of the channel 0 mapping will be created during export in order to accommodate those textures. This takes extra processing power, so it is always best to make sure that textures only specify as many different Channels as texture-mappings exist for objects which use them.
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