Without earth moving a routing could be - 1 and 2 from the Main followed by 8-6-7 on the St Olaf followed by 3-4-5-6 on the Main followed by 2-3-4-1 on the St O and then a new tee for Main 7 and would give 14 holes out in the open visible area. Add on 8-16-17-18 from the Main and you get an 18-hole routing. This would include 6-7-8 from the St O which for mortals are possibly the best holes of all the 28 available until recently at CB. Perhaps tented village on the practice ground between StO 6-8? This would give 18-holes but length and par might be on the light side.
Shame to not use the new 9th and the spectator viewing possibilities along the left of the ridge so you could revise then above, but still include the wonderful 6-7-8 from the St and instead by including Main 9, 10 tee to 12 green as a par-3, then new longer tee on 14 finishing Main 15-16-17-18.
Might need care at the bottleneck left of Main 14, say use a stop/go or one way spectator system along the left of 14 and across 15 or even install (£ though) a temporary walkway along the beach right of 14 (tide permitting!!).
Lots of possibilities - and some potential excellent spectator viewing spots - but overall yardage and par might suffer with a composite course.
The Northern Open, a Scottish Tour event, has been held numerous times at CB on the Main not a composite course, televised in part as well. The thought of 'doing something' perminent or even semi-perminent with the StO though, along the lines of recent tweaking of the Valley at Portrush, fills me as a huge StO fan with dread, but then again I'm only an ex-CB member these days, not a current one.
Atb