Could you expand on your statement that ‘the default install put it somewhere else’ please as in post #12 you seemed to imply that you had uploaded to the correct place so it would be useful for us to know if there is a problem of some sort here…
As to the base font size then this is inherited from your WordPress site theme but can be changed in the CSS file. Quite near the top in the section named ‘Main Section classes’ is the opening base #spMainContainer rules which sets the font-size to 100%. Making this percentage bigger will scale up all text content within the forum container.
As always we recommend that you create your own SP theme so that any customisation is not lost during a future update. (http://codex.simple-press.com/codex/themes/theme-basics/creating-a-theme/)
