I've build a prototype for Key Pass using a piece of vero-board with a TQFP32 packaged ATMEGA8. The board has contact pins for connection with the ISP programmer.
After assembling I've lost some hours trying to figure out why do the AVR refused to answer to my USBASP programmer. At some point I've started to think that the microcontrollers I've bought could be damaged. It was necessary to improvise a TQFP32 to DIP28 adapter in order to use the miniPRO programmer, pushing the chip to the board using a finger to grant contact. It was tricky but worked and gave me a clue about the problem.
It happens that the ATMega8 I've bought have been shipped with the option for the internal 1MHZ and for the first time since I built this programmer I needed to install the jumper that configures USBASP to operate at low speed. Now the ATMEGA8 can be programmed. I am considering to use an USB bootloader .