Nos operamur, te ludere
"Life is more fun if you play games." - Roald Dahl
The quick answer is that unless you have permission from Roxley to share those images here, they will not be allowed.
But you might trying writing to Roxley to show them what you've worked up and ask their permission -- they might be pleased and happy to share, that wouldn't be so unusual at all.
But don't be afraid to write to them -- I've found most smaller publishers are happy to have you post such things as long as you aren't selling them.