I would really like to know how did you solve this problem. I had the same as you - but I did compile perl/Tk for native Windows GUI for the previous perl version (5.6).
UPDATE:
To sort things out I did this, after upacking the Tk800.023 distribution:
- perl Makefile.PL then make with the same result as the root node.
- perl Makefile.PL x then make with some incompatible definition error.
So I was not able to compile it with nor without X, perhaps I will try soon with a fresh cygwin install (with the current one I have some permitions problems - but this is another subject).
UPDATE:
I have just compiled Tk800.024 with the patch from home.att.net/~perlspinr/perlproj/pTk.
With no X includes.