Custom segue not working

Custom segue not working

I am trying to use a custom transition. I want a "cover vertical"
transition from View Controller 1 to 2 and then have View Controller 2
(the middle one) slide back down again when moving to View Controller 3.
Storyboard shown below:
http://i.stack.imgur.com/bJYXI.png
Im using the tutorial that is linked to from this post. And have also
replaced the .m code with the code provided in the answer:
Xcode custom segue - Opposite of Cover Vertical (top to bottom) - COMPLETE
NEWBIE
I have created a subclass of UIViewController and named it
FromTopReplaceSegue. My .h and .m code is shown below:
.h
#import <UIKit/UIKit.h>
@interface FromTopReplaceSegue : UIViewController
@property(nonatomic, readonly) id sourceViewController;
@property(nonatomic, readonly) id destinationViewController;
@end
.m
#import "FromTopReplaceSegue.h"
@interface FromTopReplaceSegue ()
@end
@implementation FromTopReplaceSegue
-(void)perform{
UIViewController *sourceViewController = (UIViewController *)
self.sourceViewController;
UIViewController *destinationViewController = (UIViewController *)
self.destinationViewController;
[sourceViewController.view addSubview:destinationViewController.view];
[destinationViewController.view
setFrame:sourceViewController.view.window.frame];
[destinationViewController.view
setTransform:CGAffineTransformMakeTranslation(0,
-sourceViewController.view.frame.size.height)];
[destinationViewController.view setAlpha:1.0];
[UIView animateWithDuration:0.75
delay:0.0
options:UIViewAnimationOptionTransitionFlipFromTop
animations:^{
[destinationViewController.view
setTransform:CGAffineTransformMakeTranslation(0,
0)];
[destinationViewController.view setAlpha:1.0];
}
completion:^(BOOL finished){
[destinationViewController.view
removeFromSuperview];
[sourceViewController
presentViewController:destinationViewController
animated:NO completion:nil];
}];}
@end
When i try to run the simulator i can easily get from Controller View 1 to
2 but it crashes when i try to move from Controller view 2 to 3 using the
custom segue.
Can anyone help.
Thank you so much in advance! Struggling here! :)