What's 2D models?look,

THE buildings are very nice.With the help of my friends I know how to make it.
1.get the model Abilities\Spells\Undead\UndeadMine\UndeadMineCircle.mdx
and the skin Abilities\Spells\Undead\UndeadMine\SummonRune1.blp(Save in 32 bits)
2.Use photoshop to edite it into just like a building.
3.Remove the Alpha 1.(But i can't understand why)
Copy one of the RGB to named Alpha 1 then save .
4.Save it into blp .
5.change the skin to it of UndeadMineCircle.mdx .
(how poor my english is!)
--------my question---------
I have made some 2d models yestday.But some looks good and some looks too bright.Is that because the model UndeadMineCircle.mdx?Is that because .......
plaese save me~thanks
(ps:I'm only 16 years old in china,my english is poor

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