Hi Michael, glad to hear that you are enjoying your Printrbot Play! It is common to see some warping on the first layer. A couple of suggestions.
Use an additional fan to cool the first layers even faster. If you have a desktop fan or some other kind of fan in your bedroom, either will do the trick. Just keep a steady stream of air on the print bed as the print is running.
You could try using a brim around the first few layers to help hold them down. In Cura, select 'Brim', under 'Support/Platform adhesion type'.
- For more print troubleshooting, check out Simplify 3D's Print Quality Troubleshooting Guide.
Hope that is helpful. Happy printing!