Very helpful! Thank you!
I got my problem 2 to work (my own images, no added text, for arrows). Thank you so much!
But for problem 1: I haven't even opened the ezupsell.tpl file, I just extracted the files I got and put it in the skin1/modules/ezupsell folder. Hmm... I must have missed something, but I have re-traced my steps 5 times already (and it really isn't a very tricky installation, so I'm sure I will feel stupid when I figure out what's wrong).
The fact that the "You have added" and then "to your shopping cart" is missing on either sides of the product name (see image), what is that symptomatic of?