What are you getting in the error log on the server? There should be one in the admin directory. Also, count how long it is spinning. If it is an even number like 30 seconds or 60 seconds, it means it is hitting a php timeout.
I will add this to our bug list, but you can also install it and switch to spanish after the fact.
At the same time, where are you hosted and what package do you have? It would benefit us to test the fix out on that.
I don't think they have it, I think they choose to go with the popup method too.
I did not create any issues as far as I know, it was just seen as older technology.
It could be the image generation too. With the new fixtures I have them packaged to create the images at install. I should fix that in the next version.
We will have to figure something out about that one. What it does is download the translations from the Crowdin api, so that might be what is holding things up. MAybe we can cache them in an earlier step or something.
I don't think we will be making any merch soon. Although I have looked into it, I did like the coffee cups as well. They were my favorite, the yellow one at least.
I know of a couple native themes in development and others that are modifying their themes to support thirty bees too, so I think the theme market is going to be really nice soon.