I did make a start on laying out the char board. The problem is that you can fit max 8 x 27c322 onto a board, and then the space is tight for fix, sound and a small CPLD for de-multiplexing and banking. If you use larger flash chips you may need programming logic as well, and at some point the design is so expensive that it'll be easier to just buy an existing flash cart.We need cart PCBs like the PGM ones so we can make carts out of games like this!
Are there many games that require more than 8x4MB, or the advanced fix banking?
Downloaded teot.zip, it requires 64MB C-ROM (assuming they didn't just pad it to that size).