System Information
Operating system: Windows 10
Graphics card: AMD Radeon RX 560

Blender Version
Broken: 2018-12-19 22:35 Has: a91886e76ebd Branch 2.8

Some of the curves do not draw from the addon. It does appear the data is being created.

Enable "Add Curve: Extra Objects" in preferences
Add a curve at the 3d cursor. Some draw, some do not. Example: Curve Spirals -> Archemedian, Logarithmic, etc.