Here is what I did.
I have Plextools 1.09
I Installed Plextools 1.09, then uninstalled it, then installed Plextools 2.07
For some reason, ver 2.07 wouldn't install with 1.09 installed.
Once 1.09 was uninstalled, 2.07 installed with no probs.
1.09 must have left some refrences in registry, because 2.07 would not install without prev version, (1.09) installed/uninstalled.
I would install 2.05, then try to upgrade to 2.07.
If that doesn't work, then try uninstalling 2.05, and then install 2.07