lookslikeruck:
I'm using an Arduino UNO to program it
Did you try removing the 328P from the Arduino UNO and inserting the chip you want to program? If the UNO stops uploading that will tell you that something is wrong with that bootloader.
Try to follow this tutorial: http://pdp11.byethost12.com/AVR/ArduinoAsProgrammer.htm
It allows you to program any target AVR directely with any code you want, ex. "blink a led".
You do not really need to write a bootloader on the chip, first.
Yhep!
All seems to work just fine when loading the code with the atmega on UNO.
Does Arduino IDE needs specific preferences for this procedure?
BTW...
I saw a few days ago, an hardware "library" called "Atmega328 breadboard" but when I try to configure pin 13 (ledpin) as an output it gives me a library error...