Children's Books - do you write in British English and still sell well in the US?

I've been told that US parents and teachers don't buy children's books written in British English, but one of my books written in British English won an award in the US. I'm wondering if sales would improve if I published a version in US English.

My information is second-hand too, but what I understand is that you use your country's vernacular and a publishing editor will worry about the rest. But I guess that's not available if you've gone the self-publishing route.

Thanks.
The book was originally trad published and I got the rights back and e-published. Sales of children's e-books don't seem to be as robust as in other genres. I'm not sure if I would sell more if I did a print version through CreateSpace, or if I tried it in US English. I can't seem to get any traction with the children's books, despite some lovely reviews.

Children's ebooks are a hard sell, even in YA. Teens still seem to prefer physical books despite their love of smartphones, and younger kids don't always have access to ereaders or if they do, don't have access to a credit card. :) A print version is probably your best bet.

As to British vs. American English...I have no idea. I would have loved reading more books in British English as a child, but I'm kind of weird. ;)