Event customization

I'm currently evaluating the Events+ plugin for inclusion in my site.

Previous to giving this one a look, I had been running Calendar, which is a great little plugin and allows events to be added, but lacks some of the more advanced features that Events + has.

Having said that, when I install and configure Events +, there are some things I can't seem to get it to do.

Appearance-wise, it's not as clean looking as Calendar, and all my attempts to modify its appearance via the plugin settings seem to amount to naught (as an experiment, I tried changing the interval and the start time...no visible impact...then I created a test event and tried to change the information displayed in the tooltip...also no change.

One final note here is that the box that appears when you hover over an event (the tooltip box?) is dark gray, which is fine, but the text inside the box is a close-ish shade of gray that is difficult to read. Is there a customization routine allowing that to be changed? I did not see one, but wanted to ask.

Completely understood that some options won't work with all themes...is there a list of themes that configs have been tested with? I may jump to a new theme and re-test there!