Hi,
Compiling for iOs is not different when you use playmaker, don't worry about the internals, it just works, and you don't anything special to make it work.
I don't have much experience yet with playmaker and iOs so I can speak about perfs. but NEVER RELY ON EMULATORS for iOS dev. Don't even bother run it in the iOS simulator provide by apple. It's pointless in my opinion, unless you don't have the device with you or are doing very specific worka that do not require you to check for perfs but rather for features validation. Two reasons: the unity emulator is not totally true and give only ruff idea of how it's going to look. I have to tweak and test on the device many times to achieve the right lighting, the right shaders settings etc etc. The second reasons is that emulators ( the unity one and the apple one) are simply way more powerfull in terms fo computation speed and memory allocation than the device itself. So you are in for big surprises when you will compile on the device for the first time the day before the deadline! this is very true if you start with all this, as you gain experience and as the project gets solid and tested, you can relax a bit more and only compile at the end of the day to enjoy your app on the device more than anything else, but during the first phase of devs for a new project, I really advice you to compile and test on every single features addition.
making games in 3d for iphone requires more than just raw artistic skills, you need specific skills on low poly modeling, texturing, shading, and inspiration when problems arise. the code ( or playmaker ) in itself is a lot less important when you target devices in my opinion, the fight is really in building a 3d world using the right balance between mesh accurary, texturing, and the global feels you want to give.
Making 2d games for iOs is totally possible, but for this I would recommend using SpriteManager 2 and EasyGui. Without, you are in for trouble and will likely fail to deliver a descent work. I have done proper hard core applications for ipads in full 2d ( think keynote/powerpoint presentations with embedded 3d) and this was made possible only because of SM2 and EasyGui.
Playmaker allows you to build an entire game using just fsm and the actions provided, be it for iOS, not difference here. But this very much depends on the complexity of the algorythm you need to build ( note that I am careful not to say the complexity of the game itself, cause this often an opposite equation, that a simple game is very difficult and complex to code, and vice versa).
I would actually even say, it can achieve more than just simple games. I am currently building a full blown industrial robot simulator involving two different types of very complex robots passing parts to each other in a very specific way with many hypothesis and cases to take in considerations during the process. This would be hell on toast without playmaker, and quite simply undoable without an event system. Playmaker shines in allowing you to define processes like a flow chart does, be it industrial or "game like", this is the same. Now, to continue with my robots, I have actually built the inverse kinematics of them using normal scripts. I am not saying it's not doable with playmaker, it's just that I would need to build so specific actions that it then starts to be silly to end up with a fsm with one single state and one action ending up doing all the work. There is a balance to find ( experience will tell) between building custom actions for specific needs and building everything with totally generic actions and ending up with huge fsm or set of fsm working together. But the beauty of playmaker is that even with all the complains with make about refactoring and production workflow, it is way easier to improve a process made with too much fsm than improve a process done in pure scripts, or for that matter, a huge do-it-all custom actions: you work against playmaker way of doing things and then ends up with one state not being to dispatch useful events, etc etc.
Bye,
Jean