To completely disable the repetion of words you don't need to click on each repeat box. To accomplish this just enable "Keep as is (don't repeat words)" checkbox for "Words amount" parameter in "Layout" section.
You can select several fonts at once use CTRL + CLICK or SHIFT + CLICK combinations.
If you can't find a suitable shape for your word art you can always add your own image by clicking on the first tile in the "All" category in the "Shapes" section.
You can add a custom font by clicking on the first row in Fonts section.
You can use various icons (❤, ☺, ✈ and others) in your word art by copying & pasting the icons into Words section. Also you will need to choose "Chrysanthi Regular" font in Font column to make them appear. Please read this blog post
for more details.