you will need a C compiler of some sort, but thankfully Circle comes with instructions on how to set it up for alot of common compilers.

1) Go to
2) then the ftp site, link is on main page,
3) follow instructions, as long as you compile it on winXP it should work.

a few things...
i) I should warn you though, CircleMUD, like alot of open source projects (IMO, unfrotunately) suffers greatly from a lack of consistent coding style, different sections and patches have been written by different people with different levels of skill, different (sometimes non-existant) style, and design philosophies. PICK A STYLE AND STICK TO IT.

ii) Possibly also a redundant hint, read and understand the coders guide, read and understand the administrators guide, making changes without it is a frustrating way to go about it

iii) Invest some time in setting up a backup, or preferably a versioning system ( works well for me), so as you make changes you can always roll back to an earlier one, I would still recomend getting a Linux (of whatever flavour) and setting up a second machine, or boot option to run it, rather than windows, there are quite a few features that are for linux, and are removed at the precompiler stage from the windows set up.