Hi there! If you click on the "Options" link button next to about and then select "Recover Session" you may find the writing that was lost. As for the fullscreen issues, try going to "Advanced Settings" in the same options menu and turning off the GPU Particles setting. You will have to restart the app for that to take effect. Let me know if that fixes the issues you had with lag and instability.
And don't worry about getting it for free! Donations help of course, but I made the app available for free so that anyone could get the benefit from it even if money was tight.