[Gimp-user] [Newbie] Fill with transparent color

[Olivier Marie]

Hello all, I'm starting using GIMP 2.0.2 under winXP. It seems to be very powerfull !   I don't succeeded in filling a form with a transparent color (indexed image) My questions are :   How can I fill a zone with transparent color ? An erased zone (transparent) has an alpha value equal to 0. In the same image, others pixels can have the same index but with alpha=255. Can I have a specific transparent index ?   Thanks in advance   Olivier