When you say "import", do you mean a physical import of the data into your TW, or just an external link? Images will rapidly use up available space in your TW, slowing your TW down to a crawl.
If you use firefox browser with the tiddlyclip plugin (
http://tiddlyclip.tiddlyspot.com/) and the "local snips" feature, then you should be able to browse your file structure in one tab, right click on an image, select the appropriate snip type, and have the 2 tiddlers created for you (I think). I've never done all these steps at once. Be aware, if you try this it will take some time and studying to configure your plugin correctly -- there's a lot of options.
If the images are always in one directory, it might be easier to roll you own solution: Make a form and button where you fill in the image name, click on the button, and the tiddlers are created for you.
Good luck,
Mark