Are u using Jpg compression or png?
If what u are asking for is sprite related then it is needed to know that png has transparency embedded and jpg does not.
So in other words.
Example:
If u create a ball in a transparent box in photoshop, and u tend to use this ball in construct 2.
Then make shure u save the ball in photoshop as a .PNG file.
Then when opened up the .png file in construct 2 its transparency is recognised and u will only have the ball.
Not the white box surrounding it.
If it is not sprite related, then i cannot help u but someone else probably can.
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