Thunder Merger is an application that copies a chosen number of smaller images on a larger image surface. Has a lot of options and it’s easy to use. Useful for joining tiles or animation frames together. The root images must be numbered (egz: test1.jpg, test2.jpg, test3.jpg etc…).
RenameFile is a small utility application which numbers all the files of a particular type from a chosen folder. Use this application first in order to automatically rename all your images. Take a look at the videos on this page for quick tutorials on how to use the two applications.