For anyone following along with this thread: Caidaongtong identified an issue with the iolite v4.5.1 installer where if you select a folder other than the default during installation, it would cause a python path issue.
We are working on a fix at the moment, and will post here when the fix is ready.
So, on further investigation, if you choose a different folder than the default during installation, you will get an error when you first start iolite. You can fix this issue however by holding down the Shift key when you start iolite. You'll be prompted whether you want to reset your settings. Click Yes, and iolite should start normally.
Please let us know if this doesn't work for you.