…yup. 
Ever since Blender updated I’ve never quite felt the same about this awesome program.
And going back to some of my old games I’m seeing some of the code doesn’t work anymore…
I tried just using the old Blender but the update really took it all out of me
So I guess this is it…thought I do feel bad about it 
If the last version you used was Blender 2.48 or before, do note that there’s been a number of major changes to the BGE Python API since then (most notably the elimination of the get/set functions in favor of accessing the various properties directly and a new syntax for object properties).
Once you read through the 2.6 documentation, you should get an idea of how to port your code over for use in 2.61
How much code (etc) is there to convert? Mostly you would need a few name changes here and there, right? From what I know of Python, there were some pretty major changes from Python 2 to Python 3 (input & output commands all getting some pretty major renaming) so it might not just be Blender.
There were some good features which got lost through transitions for sure. However the new interface does work well after a while. At least they (thankfully) brought back the old method of RMB split-screen along side the new corner-window method.