Hello!
I have been off the Wick program for perhaps almost a week, and today when I reopened my project (I first tried the autosave function and then I opened my previous saved .wick files), the onion skin function would not work for my previously done animation. However, it works fine with the newly drawn things today. The newly drawn and the previously drawn are on the same frame and were drawn with the same tool. Sorry, for the inconvenience.