The "booster pump" is the red selector switch in the lower left hand compartment by the electrical panel. It will show as the 'fuel pump' when you place the cursor over it in the 3D cockpit. It also has only two positions "ON" & "OFF".
As for starting make sure you are following checklist exactly. Make sure you cycle the magneto's off then back to both. I was having an issue where the mag switch did not function properly right after startup. Have you tried the Crtl + E command which is the autostart for FS? If it works then make sure to check all of your switches. And don't forget to prime either as it makes a difference. Hope this helps.
Been turning the fuel pump on, so thats fine. Fully primed as well.
It starts with Ctl-E so it must be a switch issue.
I'll see if it's the mag switch and cycle it a bit.
Can't make out the text very well on the mag. Should it be full left or full right for Both?