SD PC version 3.6.4.0
The "2 per page" button no appears to have no effect now. It prints a full A4 page regardless of whether it's selected or not.

We are unable to reproduce the issue you describe. Please could you give some more details including exactly which screen you're in, and what you're trying? Possibly what route you have planned, in case that is relevant. Thanks.

Hi Tim
I've tried with several different routes and the result is the same, but for instance, Shoreham-St Catherines Point VRP-ORTAC-Casquets VRP-Guernsey.
With the route loaded, I click"Pilot Log" and SD creates a landscape A4 page. Clicking "next page" displays the next page.
If I click "2 per page", instead of creating 2 side-by-side A5 pages which will print on a single sheet of A4 (as in previous versions), it  reverts to displaying the first page (landscape A4). When I click "print" I get 2 A4 pages, instead of 2 A5 pages on one A4.
I have tried this on my desktop PC and my laptop (both running Win7) and the result is the same.

****SOLVED****
I changed the page margins to 10mm, now it's fine.

If the page size available for us for printing is not large enough, our two per page feature cannot kick in. It sounds like that is what you were experiencing.