Chalk Paint Nightmare

Submitted to Community Café

Help please!!!!! I have been working on my grandsons puppet theater since before Christmas!!! I feel like no matter what I do I end up with areas that are darker than others. The top coat doesn't look even either. What am I doing wrong??? I just want to finish this. It was supposed to be a fun project!!! Thank you all for your help. You always come through. I used a Purdy paint brush too. Should I have used one of those round fat brushes???