Umm, I have no idea but you might be able to manually upload the files of certain "species" and if and adoptable is a certain species, you can try changing the code on the levelup and myadopts pages to get and adoptable's type and level and then insert that value into the filename which should have a matching file in a separate folder... (I'm pretty sure you won't understand what I'm saying).
For example:
Put your files in a folder and name them: species namelevel.filename
Edit the myadopts and level up pages to get the function to select an adoptable's species and level.
Put those values in a variable.
The do something like this:
<img src='{$speciesvariable}{$levelvariable}.swf'>
I tried this with a system I'm using. I'm almost 100% sure that there's another way to do this that's 1000 times better, but I barel know any coding... I can maybe try this for you, but I have no idea how an swf file works. XP