I am using a tool named "AVR I/O-Design" from a website named forestmoon.com
This tool has been updated in 2009.
The tool generates good working header-files for easy access to all kinds of ports and features inside a AVR. also it calculates timer, UART and some more settings.
Is there something like this on the market - preferably with close integration in AS 6.1 and with support for "modern" AVRs ??