wavy lines

[Acorn]

as the issue is sending to a printer I've never seen the need to do anything other than set print as bitmap in options, at least up to A3 print size
if that affects anything else, adversely, I don't recall ever noticing it

@handrawn, the Help states:

Print AsNormal is suitable for most types of document.
However some printers do not reproduce consistent colors when printing bitmaps or vector objects that are the same color (this is a fault with the printer driver).
This is noticeable if objects overlap onto bitmaps or onto objects with transparency applied to them.
In this case, select Bitmap or Anti-Aliased Bitmap and retry.
The choice between Bitmap and Anti-Aliased Bitmap depends on the printer and personal preference.
Some printers give best results with anti-aliasing turned off especially when printing thin lines.
As a rule, using anti-aliasing allows lower resolution printing.
For example, 150 DPI bitmap printing is usually good enough for all uses-even typesetting.
Without anti-aliasing, higher resolutions may be needed which gives much slower printing.

My worry of using Anti-Alias Bitmap is it might be fine for screen viewing but it probably fudges crisp edges in a print.
Equally, Bitmap suggests to me that that is a mapping of the image dpi to the printer resolution occurs that again may affect edges.
Instead, I would be looking at printer driver settings or print via PDF.

Acorn