yes...i would always recomend atleast 2 % castor..this is acturly quite normal in most synthetic fuels,,between 5 to 15 % nitro is about corect for most 30 size engines..
when you do start it and run it in make sure you run it rich ..
is it the ring version or an 'ABC' ENGINE btw?????
as a ring engine requires a diferent method to run them in then the ABC engines..

the genral rull of thumb to run in a ring engine is .
run very rich for 1st tank, then each tank after that move the needle valve slightly to make it slighty less rich..dont let it peek out though untill aprox 10 tanks.......

abc engine.... run very rich 1st tank, then next tank start engine and peek engine for 5 seconds then richen up run at rich for aprox 30 secnds and peek out for say 10 seconds, then richen up .... repeat this but lenthen the time of peek running by aprox 5 to 10 seconds ..when you are peeking the engine for about 2 to 3 mins then the engine is pretty much run in...even so i proberly would still run it a tad rich for a few more tanks...
oh with this metod of running in ( for the ABC engine ) i was thinking you might do it by putting the engine in a test bed and put a propeller on it..this is how i would run mine in any way but if you have headloaders then you can still run it in on the heli.. you can run an engine in from the start on the heli but i always prefere a couple of times on a test bench 1st with a propeller..

hope this is of help.. there is a couple of ways to run engines in but as the saying goes ' there is more then one way to skin a cat '