The top of RnallViewer's main window lists information about the annotation file -- name, start and stop position, entries, and a current scan section of the sequence file. On the top row, the name, number of proteins and start and stop locations come from the current annotation file loaded. RnallViewer understands protein table format (.ptt) and gbk. Below this is a sequence viewer, which displays and lets you save a specific subregion of the fna file. Hitting the <- and -> buttons will scan back and forward one position, preserving the scan size. Type in a start and stop position and hit rescan to display a specific subregion. Hit save to save the subsection.
When you load a new file, RnallViewer checks it's type. If it is a ptt or gbk file, the annotation information is generated from the new file. This also creates the categories in which you can search, generated as the union of category types of each entry. Simply selecting an advanced search will let you see all the categories generated. Also on the main screen when you higlight (mouseover) or select (click) a gene it will show annotation category information at the bottom, dynamically generated based on what category information that entry has. Not all entries need have the same category information.