Following on from http://atariage.com/...eck-2-512k-ram/
I have tried out various configurations of MyDos and the RamDisk drivers together with a Sys-Check 2 card, and have managed to get it to work as a 512K Ramdisk.
I ended up using MyDos 4.53/4, as this is supported by dir2atr (MyDos 4.55 isn't supported by dir2atr).
I used the MYRD2 ramdisk driver, which is part of MYRD.ARC (written by Lee Barnes).
I've attached a working ATR that should be good for anyone to use with a Sys-Check 2 card (I followed the instructions in the Ramdisk readme, and wrote the Dos files back to disk after booting with the Ramdisk driver).
The files on the disk are:
DOS.SYS, DUP.SYS - MyDos versions
MD.ARC - Compressed Disk Communicator image of MyDos
MYRD.ARC - sources and ramdisk drivers
DISKCOMM3.EXE - disk communicator 3 by Bob Puff
MYRD2.AR0 - the Ramdisk driver that works with SysCheck 2 for 512K Ramdisk
UNARC.COM - super-unarc by Bob Puff
Thanks to all that helped, I got all the files from http://mathyvannisselroy.nl/mydos.htm - I've just combined them into a single ATR for ease of use.
Hope this helps.