I don't see the problem of the patch not working. You can always create a blank hdd image (Boschs emulator has a windows command line utility to create such image, 25-30 MB size oughta be enough) After that just use original dos 6.22 install disk or any bootdisk to format the image blank to FAT and copy all the needed files there in. (Pay attention to image creation too, as you need to temporarily use sector,head,cylinder format for imgmount until you have formatted the image); then you would just do 'imgmount c <filename.img>' followed by c: and what ever command you would want to run in dosbox. (I use such approach to play monkey island games and stuff like that.)
For Gravis, I think its disabled by default in dosbox.conf so need to edit there as well.