Hmm, i just tried my own workflow advice using a model more complex than the cube i was using and found it didn't really work that well.
A good way of unwrapping a model is to work methodically, unwrapping sections at a time, here's my take on how to do that in wings.
1. use the polgon face selection tool to select groups of polygons with a similar orientation
2. Right click on a selected face and choose UV Mapping->Direct. a new window called AutoUV Segmenting: appears showing you a view of your previously selected polygons.
3.Use your mouse to adjust the viewpoint orientation of the 'AutoUV Segmenting:' window so that the polygons face the camera as much as possible, we're doing this as we're going to unfold these polygons using 'camera projection'* so aligning them with the camera is going to minimise any distortion & streching in the generated UV's.
4. right click in the 'AutoUV Segmenting:' window and choose Continue -> projection camera. A new window will appear filled with coloured squares and your UV 'islands'
5. using the space bar to deselect and the 'object select' button (the red cube at the top of the window) start selecting UV islands and moving them off the area of coloured squares and into the neighbouring areas, try to lay them out so they match your model - it will make painting the texture map easier.
6. close the UV map window and go back to your model, select some more polygon faces and continue unwrapping your model (jump back to step 2 above),
7. place your new UV's next to your already existing uv's,if required scale and rotate your new UV island to fit.
8. once you've unwrapped your model completely, move all the UV islands back into the 'area of coloured squares', make sure they all fit in the area of coloured squares - there can be no bits left poking out as i belive you will get problems when converting your obj to a dat
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* an alternate to camera projection unfolding is polygon normal unfolding, this might work out to be a faster method as there is no need to line up polygons with the camera before unfolding, and you will also be able to unfold polygons with different orientations all at the same time:
eg, here i've selected a U shaped group of polygons that make up the models 'nose'...
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...i'll unfold them using 'projection normal'...
...as you can see something has gone wrong - the side polygons have smeared horribly, if you look at the generated uv's you can see that the UV's that correspond to the problem areas are very thin indeed so a small amount of texture is being spread across a rather large polygon, to fix this we need to edit the uv map - use the edge selection tool and the move command to edit the problem UV's, keep an eye on the texture in the main viewport to see what effects your editing is having, you'll want to get the 'squares' as square as possible and the same size as the other squares.
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