Single line font not displaying 'i' or 'l'

[Kristyj04]

In Affinity Designer I am trying to use single line fonts for laser engraving.  These are fonts with no closed path.  When using a sans serif font the letters 'i' & 'l' do not display. There is an obvious space where the letter should be, but it is not displayed.  All other letters display correctly.  Behaviour is identical in V1 & V2.  Cursive or serif single line fonts all display correctly.  IT seems to be an issue when a letter contains only 2 nodes.  

Running OS X 12.6 on M1 MacBook Air

[kenmcd]

What font are you using?
We may be able to modify the font to add some nodes as a work-around.

There have been some discussions here regarding Designer, by more experienced users than me, where the issue was worked-around by adding a node to a straight line. I cannot remember where that discussion is located. Maybe someone else will.

But we can try modifying the font if you want.

[Kristyj04]

That is a decent suggestion.  Do you know of any good applications I could use to modify the fonts myself? A couple of the fonts I am trying to use are below.

CNCHero-TallandHandsome-Regular.otf

Gretzki.ttf

408876-bfc-homestead-simple-sans-sketch-font.otf

[kenmcd]

42 minutes ago, Kristyj04 said:

Do you know of any good applications I could use to modify the fonts myself?

Single-line fonts are a bit unusual and I have little experience with them.
Glyphs App can handle single-line fonts with a script I think.
Robofont does with a script from GitHub.
Maybe FontLab 8, but I have not tried it yet.
FontCreator does do single-line fonts.
Do not know of any free applications which can do it.
How do people usually make them?

Tall and Handsome does appear to be a free font. (looks like CNCHero renamed it)
https://k40lasercutter.com/product/tall-and-handsome-single-line-font/

But I do not want to register to download it.