Q: Ran 'repair disk' from disk utility, now unable to boot into win8 partition

That's not normal.

Please do a ctrl + c which should quit the program and dump you back to your normal terminal prompt.

Then re-open gdisk

sudo gdisk /dev/disk0

type p and hit enter.

What's the output of that please?

Ok thanks. Start again from the "type r and press enter"

You may possibly have hit a double space or something when entering partition numbers.

Ah ok. Safe journey.

I'm in UK so may be in bed by the time you get back.

I'll have a think.

I tried to post this 3 or 4 times last night before I went to bed but there were problems.

Instead of entering 2 3 4, try just 4 and press enter.

Still answer Y to adding the EFI partition as first entry

Accept defaults for partition 4 though making sure that the type code is 07 (if not type it in manually)

and answering Y to making 4 bootable.

Answer N to protecting other unused space.

Type w and enter to write the changes to disk, then q to quit the program.

Reboot holding Alt and see if Windows appears in the boot menu and if it does try to boot it.

You could run Windows automatic repair from the installation dvd/usb. It may need to be run up to 3 times as there can be 3 repairs to do.

It may not be as easy as rebuilding Windows. It may be the case that Bootcamp Assistant may not allow you to remove the Windows installation and using disk utility to remove the Windows partition is a definite no-no.

See how it goes.

I suspect the damage was done originally when you attempted the resize.

I also suspect that you haven't tried to boot Windows since you upgraded to 10.9.1 and it is that upgrade that has stomped on your Windows partition as it didn't find what it expected to and panicked, in that it wasn't the size it thought it should be.

The problem is, Macs using Boot Camp have two partition maps, GPT and MBR. Normally they're in sync, so they contain the same information. GPT is used by OS X, and MBR is used by Windows. Windows resizing tools, including Mini Tool, only change the MBR partition map. So then it's out of sync and the first casualty is that while Windows will still boot, its Boot Camp volume won't mount in OS X because its GPT partition entry is wrong while the MBR is correct.

When you used Repair Disk in Disk Utility, it assumes the GPT is correct and creates a new MBR based on the GPT entries. And it creates it wrongly by using type code 0C and it doesn't mark it bootable. Utlimately that's what caused the problem. Apple tries to get around these issues in their documentation and online support documents that proscribe resizing Boot Camp. http://support.apple.com/kb/HT5639

How can a Windows partition be resized after Windows is installed?

You need to delete the Windows partition using the Boot Camp Assistant, and start over to change the size of the Windows partition. Back up your important Windows files first.

So how do you fix this? There's nothing to go on in the MBR or GPT because the repair made them the same. So the critical information needed was in the old MBR iand it's been overwritten with wrong information and there's no way to get that back. What you can do is use testdisk. It will find NTFS superblocks and figure out some plausible start and end sectors values for the old partition, there may be more than one suggestion but only one will have a List Files option. Make a note of those start and end sector values for that guessed volume; and then use gdisk to delete the bogus Windows/Boot Camp partition #4, create a new partition #4 using the values from testdisk, use type code 0700 when asked. Then create a new hybrid MBR also in gdisk, adding partitions 2 3 4 and making 4 bootable. Then write out the change. Then reboot.

If you specify adding partition 2 3 4 and yet you get "Use one to protect more partitions? " that means you answered the very first question "Place EFI GPT (0xEE) partition first in MBR (good for GRUB)? (Y/N):" with N. That needs to be Y. But in any case the first thing you need to do is use testdisk because none of this stuff in gdisk will help until you get the correct start/end sector values for the 4th partition/Windows/Boot Camp volume.