I saw your Twitter post so this might have been sorted out already, but replying in case it helps other people as well.
Which renderer are you using? I've only really tested with Blender's internal renderer and the quick material setup is really designed for an unlit look. The material settings may have to be changed to use the Cycles renderer or for a differently lit scene.
The work plane being stuck on a single axis sounds like Axis Lock might be on. It's not covered in the basic tutorial but the written advanced tutorial does. Basically the toggle on the left of the axis indicators in the Sprytile panel.
Sprytile's tools are untested with subdivided meshes and is not really designed for that use case.
This style of rendering is really neat and an unexpected use of Sprytile for me! Would love to be updated with how you push these renders.
Thanks for using Sprytile!