Its been awhile since I needed to print something at an exact scale from Photoshop so this may not be correct but I remember just setting the "pixels per inch" to be what I wanted and printing at 100% scale. For example if I was making a 8" x 8" square room and I wanted 100 pixels per inch resolution I'd just pick 100 pixel per inch and make the image 800x800 pixels or 8x8" inches.
Dundjinni is a neat program for people who either either lack the skills or time to make maps of that quality any other way. The best looking Dundjinni maps rely heavily on photoshop or gimp for either touchup work or for creation of the various elements used. This is not a knock on Dundjinni at all, it is a great tool for an average person to produce exceptional results with. It just relies on people wth exceptional skills to generate the content everyone else uses. The user art submissions are great on their site are a great asset and can be used in photoshop just as easily as they can in DJ. So purchasing the DJ software or their art packs are a good value even if you don't plan on using DJ to actually map with. You get alot of art you can either use directly or use to hone your own skills in trying to replicate or alter.
Personally I use
Map Tool for playing on my creations since it skips the whole printing out or taping together large maps. I even have access to an HP designjet 500 24" wide roll printer but I like to stay digital
Overall I my graphics art collection includes Photoshop 6, Photoshop Elements 2.0, Corel Painter Essentials 2, a Wacom tablet, Bryce 5.5, Poser 5, DAZ Studio and wings 3d. Since I am a mechanical design engineer I do 2d and 3d work all the time as well using both AutoCAD and Solidworks, both of which are able to output formats I can work with in the more artsy programs. I use AutoCAD for my vector work like doing ship deckplans and occasionally will model things in solidworks that would be a pain to do in a subdivision surface modeller. I also have Campaign Cartographer with all its add-ons but the Fast-CAD system they use as a core has got to be one of the buggiest and slowest vector apps I've ever used. I'd use AutoRealm before I'd waste any time with CC Pro if I didn't have AutoCAD.
I only mention the 3d modelling aps because it seems like that it what most people who submit art to Dundjinni's website are doing. Making or buying 3d poseable models and rendering them from a top view and them cleaning the result up in photoshop and adding the alpha channel and shadows to smooth edges. DAZ Studio is a free download by the way and you can find lots of free 3d models on the net to plug in, pose up and render away for making your own png content for photoshop or DJ.
