Michel,
I'm very happy you are progressing since the last time we communicated.
Was the info I sent you helpful in finding the products you required?
Honestly, you will find, the more bricks you make, the more you will want to make. It's very addictive to see a large pile of finished blocks waiting for you to create something.
Take your finished blocks and play with them before you glue them. Set up a design on paper or in your head for what you want. If you are going to make a small building, I was suggest a base or platform. Smooth 1/4" plywood or any thin sheet wood will help.
You will learn tricks along the way to go much quicker too.
I'm sending you a link that will help you get rid of those bubbles.
http://www.hirstarts.com/casting/advanced.html#wet
It's a very simple process. Just spray the molds.
If you need any assistance, please ask, I can either explain it or send you the link you need.
I'm so flattered that my meager castle has inspired you to create. It's comments like this that really inspire me. Thanks.
Good luck, again, if you need any help, just ask.
Michael
PS...Here are a few pictures of extra buildings I made from the leftover blocks. Perhaps it might be more rewarding to start with something smaller your first time. The hydrostone is so cheap, mistakes cost you virtually nothing.