Tried the search, didn't find the same problem so here I go:
Unrarring to different folder does not work. Downloading is set to "D:\Downloads\Usenet". "Unrar to different folder" is set to "I:\Usenet". (also set "Create subfolder based on NZB name" and "based on archive") But still the downloads are extracted in the same folder as the downloaded files. However when I select "change unrar folder" for a specific download it points to the I:\ drive.