First download KDiff3http://sourceforge.net/projects/kdiff3/files/
You will have to download again the original version you have.
For 5.5:http://download2.kitopen.com/kito%20source%20debug%20v5_5.7z
(If you have a different version ask redeye.)
Then download 6.0:http://www.kitopen.com/t532-download-and-instructions-compile-your-own-it
(You will need a bit of knowing on how to edit the source and such, I will not explain everything.)
kdiff3 adds a submenu to the context menu when you right click a folder. kdiff3 => Save for later
So go to the original version and find the src folder and right click => save for later

And then go to your own IT version's src folder and "Compare against"

Then something like this will open:

Click on Ok and navigate in your client folder and expand more until you get files,
double click a file one of those with differences (red/green)
Now you can start copying those differences over to 6.0
notice about 6.0:If a difference is shown in
MagixCampaignManager.h, then look in
MagixCampaignManager.cppnotice that 6.0 requires
VS 2013 community editionBTW: If you use 5.5 version you SHOULD really update to this new version, It has a working raknet and your connection problem/crash will be solved.
If you have any questions/issue feel free to ask.