1) As you can see, after installing version 1.5.0.63, there is no DiskTree tab.
If you are getting the trial expired message, then that's normal. If not, then you are, probably, using a bad cracked version.
2) The charset dropdown list is using bold fonts. What font should be in there and what encoding?
I've now made some changes, for possible causes for that problem, but I don't see it happening here. For Eastern Europe languages, you should have in that charset option the EasternEurope_Charset or Default_Charset. But it is set automatically, when you select the interface language.