I'm new to and very unfamiliar with content creation, but being dissatisfied with all of the non-multi-PT hacks available (I only need one), I decided I should try to create my own. Following this tutorial , I've run into some problems.

Steps 1 - 5 went smoothly, but on the 6th step, where I was instructed to extract two images under the jpg/tga/png Image selection, only one was available. I tried going on anyway, but there was no "Add..." option under the File menu once I'd created a new file in step 7. Attempts to "open" instead were met with warning messages telling me that Spore files (I'd tried to "open" an .xml) were not supported in SimPE. Can anyone help me? Would this question be better-directed at the SimPE support site?

Your best bet is to post your question in that thread. That way the creator will see it and likely be able to help you with it.