I have an old Mac to create the certs etc but I have heard of people using VMWare and a Mac OS image from a PC.
Anyways, other than the certs, the following has worked for me on 5 iOS apps. As stated, apologies if this is already known:
My problem was:
xCode and Ejecta process was a pain and only supported banner ads. Ejecta export in XDK would not build for me as iOS. So I tried building an Android export to XDK as an iOS app in XDK. The preview sound did not work and neither did the builds sound on an actual iPhone.
After playing around with multiple C2 exports to XDK the sound in my app suddenly worked! I retraced my steps and found this to be true (for me):
1. From C2 (with admod plugin details for interstitial in place), export an Ejecta set of files to the waiting XDK 'www' folder.
2. From C2 (with admod plugin details for interstitial in place), export an Android set of files to the same waiting XDK 'www' folder.
3. From XDK, build the app as iOS.
4. Test and run on a device.
5. Sounds and Admob interstitial ads now work in an iOS build from XDK.
It seems the buildable Android export overwrites Ejecta files but some Ejecta files are not overwritten and those files handle sound.
Anyways, this may be known but this process worked great for me and I have successfully submitted apps (with interstitial) to iTunes Connect using it
I was using the xCode/Ejecta method and that drove me crazy. Took longer than actually creating the app.