Font compatibility with Office (for Mac and Windows)

Question

Hi,
Despite extensive searching, I'm struggling with a font compatibility issue between my Mac and my colleagues' PCs. The main points in order:
The fonts work correctly on both my Mac and other PCs.
The font in question is HelveticaNeueLT Std, rolled up into which are several different weights. The files are OTF files. The same files install without any problems on all the computers in question (and show up in Font Book). And the font can be used successfully:
- in Keynote, I select Helvetica Neue LT Std, and underneath choose whichever weight I want
- on PCs, the font and weight can be selected from the drop-down list in MS Office.
- in Office for Mac 2016 (Preview), I cannot select the font from the drop-down list, but can hit Cmd+T, and then select the appropriate font and weight under 'Latin text font'. What is odd is that in the dropdown list, only a particular weight/typeface is shown:
As this is a preview version, I wouldn't expect Office to work perfectly just yet...
When a file is created on a PC, it works fine on my Mac.
Every file I have attempted to open that was created on a PC, and using these fonts, works fine. The fonts display correctly (i.e. including the correct weights), and I can work with the document without any problems. The only odd bit: sometimes in the dropdown box on my Mac it then says (null):
Whereas at other times, the font name shows correctly:
Both of those examples were created using the 'Thin' weight of HelveticaNeueLt Std. I can't see any pattern as to what causes this inconstency.
The problem is that what I create on my Mac shows incorrectly on a PC.
If I create anything using Office 2016 or Keynote, selecting the preferred weight as described above, it shows just fine on my Mac. But when I send the PPTX file to a PC, all weights look identical (it looks as though the PC has just displayed everything in a standard weight). This is the problem I am trying to solve.
To try to get around this, I tried the process of removing the Helvetica/Helvetica Neue .dfont files that come with the Mac - but this didn't work and caused several other problems. Besides, the font I'm trying to get to use as intended has a different name.
All help would be greatly appreciated - my thanks in advance.
John

Answer 1

Thanks Kappy and apologies if it is inappropriate - but just to clarify, my main question is whether fonts used in Keynote should be compatible with other software (in this case Office running on Windows). The Office for Mac Preview is a bit of a red herring but I thought it should be mentioned.
I tried to clarify my first post, but it didn't work. What I wanted to add was simply whether Keynote handles fonts in a way that other pieces of software struggle to read - despite the font itself working perfectly in both environments.