Hmm, I suspect you are right, thank you for the feedback. I think my customers will be business owners with some technical expertise (you need to at least understand what a transparent PNG is, and be able to paste it on your background), but I don't want to discourage end customers. I need to think about enabling map creation without accounts. I am requiring accounts now because you'll have to design a theme before you make your map (star colors, labels, fonts, etc) and I am assuming you'll want that to be saved. But I could make it optional...
You could also build up a temporary pseudo-account based on an anonymous user's session that could optionally be upgraded to a permanent account with an ID and password at any time.
This is common with e-commerce sites. Many don't require you to make an account to add items to your shopping cart or even to check out. But if you want to make an account, they make it super easy prefilling info they already have, and they certainly won't make you lose what's in your cart.
Another customer segment you could go after: I generated the star map from the day/time/location of my wedding, and themed the colors to match the wedding colors. My wife thought it was a great idea to print + frame it.
