Make the tray selection in the Paper Size/Type Dialog (File:Page Setup...).
A setting there overrides any you make in the printer driver (after [Properties[).
I think I may have lost something in the translation. When I go to Paper size (File:Page Setup.) I only have 2 tabs, Page Set Up and Layout. Page set up only gives choices to the size of the paper, paper orientation of portrait or landscape and margins.
The tab for Layout only gives choices for double sided printing which I don't have.
When I go to help it send me to the printer commands.
If I set the printer command for Paper Source - first page - to auto-select and second same as first page> OK that Paper Source reverts back to manual when I close and go to print. Then when I open the print properties again Paper Source Fist Page is set for Manual.
If I set both commands [first page and other pages] for Tray 1 it still reverts back to manual.
WP interrogates the printer driver. The options it offers are those that the printer offers. So
1) select the printer
2) File>Page Setup - see that [Printer page types] appears in the Page Definition Box
3) create a Paper Size/Type just for that printer, selecting the Source. (If you highlight an existing P_S/T, its dimensions appear after [Add]