The individual Simple* modules' Subversion repositories have been merged into one master repository. The individual ones are still present for the time being, but are not being updated. You should check out the new master repository as soon as you can.
To download the entirety of simple* into a new directory (it'll create a directory called "simple" in your current dir), use:
svn co https://www.cs.binghamton.edu/svn/simple
Then you can work with the files in that directory.
Before you do any work with it at each sitting, update it by entering the "simple" directory and using:
svn update
This will make sure you're using the current version. You'll also want to then run "make" (and perhaps "make win32") to be sure it's all up-to-date.
If you've made modifications and want to submit them to the developer, first update the directory as indicated above and resolve any conflicts, then if you've added any new files you must add them with:
svn add filename
Then, once you are sure all the new files are included, use:
svn diff > myfile.patch
Where myfile.patch is an appropriate name for your patch. Then gzip it:
gzip -9 myfile.patch
Then send the developer that gzipped file (in this example, myfile.patch.gz) as an e-mail attachment with an explanation as to what the changes are for (hopefully before this, you've already talked with the developer about these changes).