DSimien

Thanks. Now I know what to do. 

Hi DSimien,
the pre-launch beta isn’t functional anymore. You can safely remove it from your system. The launch version is an entirely new installation that doesn’t require the beta to work.
Future customer betas will sit alongside the official versions and won’t interfere with them. 
Hope that helps …
Alex

At last!! Thank you for Publisher!
My first thought was how do I import my indesign files? At the moment there is no 'Import' button and 'Open' an indesign file shows a greyed out 'filename.indd'. Hmmm?? But because I always create a pdf from my indd files, I found I could 'Open' the 'filename.pdf' with no problem other than it opens as pages not facing pages. I then clicked the 'Document Setup' tab and changed the 'Layout' to 'Facing Pages' and I now have my indesign page saved as 'filename.afpub'.
Good news!

I can't give any timelines for this (IDML import, not INDD). It's being worked and will be in an update when it is considered working and relatively stable. But I would be talking more than a few weeks in not months, It's not a simple thing to just implement 
(edited by Patrick Connor for clarity that this is a statement about IDML and not INDD: 08 July 2019)

At the very least, importing IDML files is a must. Scribus and VivaDesigner both do this, and it's the only way to get punters to switch, if they've got legacy documents.

@Chris_K
Is there any planned timeline for this? Are we talking months, years?

Great to hear, because it will be a pretty important option in my opinion 

@Gabe Logan
Welcome to the Serif Affinity forums
It's not possible yet. There are plans to be able to open IDML files in the future
<mod edit> IDML not INDD file clarification was made in an edit on 6th July 2019 </mod edit>