i downloaded the original MSDN iso files of windows 7 ultimate x86 and x64, if i delete with "ultraISO" the ei.cfg to bring the all other versions of windows i will not corrupt the iso?
All editions will be available and you wont corrupt anything. I did the same with both iso's i use from msdn.
I noticed issues while trying to install windows via usb when the ei.cfg was deleted.. it wouldn't let me boot the setup and had to put it back on and just edit the version manually
Just in case you don't know when you load an ISO into Ultraiso you can delete and add files then burn dvd on the fly you don't need to save the modded iso .
Ei.cfg Deleted EI.CFG on both x86 and x64 burned to cd and loaded to FDD.. no problems with anything been running it on test pc's with no problems