I just bought some Audio Pro Unlimited licenses for a few Music Maker Jam sound settings!
For the songs I made with the soundpools covered by those licensed settings, am I allowed to sell those songs to be used in someone else's projects (ie advertising, films, etc.)?
In general you can use the Audio Pro sounds for commercial use, however there are limitations/ conditions so you must check the individual terms and conditions for each of the Audio Pro soundpools / styles licences on the Catooh site.
You may also have issues with others claiming copyright on music also created with the same soundpools.
Having similar sounding music using the soundpools is inevitable unless they have been extensively edited - from a Pro licence.