Have not installed this, but want to give a quick comment...
I've learned my lesson with appearance and/or OS enhancement tools... the benefits are usually very minimal, and when they cause problems (of which they often do), the problems are big.
I run everything lean...in fact, if there is an installer that's beyond the "drag to your system folder" type, and it's not Apple, I usually discard. My G4 hasn't had the SLIGHTEST bit of trouble since I started this practice, and I'm going to stick with it.
Again, just a comment and not a review on this app.