3.021 is ready for download.
I have fixed a bug that apparently crept into 3.019. This bug could show when inserting a control line that begins and/or ends with a spider web center. The bug prevented the completion of a spider web center auto stitching. Unfinished stitching can be fixed manually but this is not so friendly for a beginner, which is why 3.021 has been uploaded so soon. 
Another not so problematic bug relating to inserting control lines has been fixed for 3.021. This bug only affected the preview line when inserting a looping control line. It did not affect the end functionality but could make things confusing for the user.