Hi!
Once you’ve installed the Revolution slider, you need to create a slider. Or if you don’t want it, use different page template (there is a default page template that you can then customize – choose sidebar, no sidebar or full width page) that doesn’t have revolution slider. The error you got is because you don’t have a slider on your page, and the template you’re using requires it.
What error did you get when choosing the transparent header exactly?
When editing theme options, please use only the menu Vozx options (the one with the gear), and not the customization from Appearance menu. There are a ton of options in there – logos, favicon, colors etc.
Text color, as in the text of the entire page? We have never thought about it, but it wouldn’t be hard to add – you’d add a text color option in redux.php found in inc folder in the color section, then edit the colors.php to add the text color section that picks up that value from redux, and then you’d just target all paragraph elements.
