Can I ask what TC package are you working with, i.e. designer, deluxe, pro, pro platinum.
also if deluxe or pro, which draw mode are you working in, (options menu - native draw, GDI or RedSDK), if deluxe/pro and set to RedSDK and drawing 2D, it may be better in GDI mode which is the same as v17 will have been in, but unless you purchased Lightworks one cannot quality render 3D in GDI mode.
Sorry for questions but there are quite a few TC options available these days.
You could post a file for someone to check