1) The layout shows 1206 size passives. A resistor and capacitor kit can be purchased from here which should last a while. I left the transistors and electrolytics through hole though because they are obviously much less fiddly than SMD (the transistors would be awkward to use with vero and hard to place on 3 consecutive rows) and of course everyone already has a good selection in stock. This is for an NPN silicon build, but it also means it could be easily adapted for a PNP germanium.
2) Solder the space you intend to put the component in first. Then all you have to do is rest the components on the solder (preferably under a bit of force, maybe with a cocktail stick or tweezers), and melt the solder. Finish off afterwards as necessary.
3) When the components goes over the top of a track cut you'll need to keep the cut as small as possible. It may be better to do them with a Dremel or similar rather than a drill bit. Check for no continuity with a multimeter before you solder over the top.
4) I haven't shown through board track cuts on the top side of the board to avoid any confusion. You can still use the links as guides when placing the through hole components but I thought it better like that. Then if you see a track cut you don't have to think about it and know you're looking at the copper side of the board.