Thanks for response.
Just to clarify doesnt the Pistorm take over the onboard Roms making them obsolete? The rom file on the pistorm becomes the latest? I have my pistorm all partitioned and I have managed to copy some software over to pistorm hard drive but if I remember correctly not all software runs from work bench. Do I have all this correct so far?
Sorry these are total noob questions 
Going to have a look at YouTube link now.
ROM files stated in config txt will take over from onboard ROMs. No not all software is DOS, alot of disk based stuff have custom code that make them non dos disks.
If its games, you can use WHDLoad to run non dos disk games from HDD.
