Cas is a small, simple and reliable application that createsa thumbnail or contact sheet of bmp, gif and jpg files in a directory.

It will automatically resize the smaller images to make most efficient use of the larger sheet.

One way to use it is to run the exe, and pick a folder you would like to image.

The other way is to run the .reg file in the zip file which puts an extra item
on the menu you get when you right-click a folder in Windows Explorer.

Once the folder has been selected, you can choose some options like output image size, background colour and quality. The larger the JPG quality number, the larger the resultant file will be, but the better quality.

75 is the default - explore if you like to find what best suits you. The default output file is named "00_index.jpg" in the directory you've chosen, but you can change it at this point.