The syntax checker is now set for practically full Scheme. It now permits set! and many other mutators, do, begin as well as having multiple forms in implicit "begins". It still requires cond and case forms to have an else clause, but does not require if forms to have an alternative. It does not permit procedures with a variable number of arguments --- this is currently a limitation of the way I wrote the syntax checker and is not a setting that I can easily change. Same goes for "named lets".
If you organize your code as I have suggested, you will have 2 files. You'll upload each file to two different web testers. You could put your code in four separate files or all in one file --- you only need to submit code for the respective problem for each web tester. That code however, must stand alone ---- any procedures it needs (that are not in the support code) must be included in that file.
This web tester is for uploading a working evaluation function. There will be a separate web tester setup for the Connect 4 tournament.