Question about Uaxis and Vaxis

Since I have JUST finished writing a simlar program I know all about them.

They define the x (u) and y (v) basis vectors of the texture in 3D space. If u is [1 0 0 0] it means the x axis of the texture will face the positive x direction of the real world. (The final digit is simply an offset).

So if you have a face with normal (0 1 0) (a face in the xz plane facing +y) you will want to set the u and v axis to two vectors that are orthogonal to your face AND to each other(I think they can be non-orthogonal to each other but for 99.9% of cases they must be) so you'll want something like [1 0 0 0] for u and [0 0 1 0] for v.

If you wish to rotate the face's texture, you must perform a rotation around the face normal. This keeps the u and v separated by the same amount and simply points them in different directions.

If you wish to scale a texture up in one axis only, apply a transform to both u and v that is simply a scale along that axis, the 0.25 defines the overall x/y scale but scaling the u and v axis can perform a shear to the texture, this is that 0.1% of times.

Here I have assumed you understand basic maths like the scalar and cross product as well as definitions of stuff like orthogonal, If you don't get anything I'll point you in the right direction.