[lost_]

LOL - I found a workaround just after I posted this. I created a shortcut ##778#.lnk to the command line "\Windows\epst.ext ##778" using File Explorer and Total Commander:

First with file explorer, I found \windows\epst.ext, then created a shortcut to it on "\Windows\Start Menu\Programs\System Tools" folder, and next with Total Commander, I hold-tapped the shortcut file, and went to its Properties menu and added ##778 to the on the target tab (not ##778#, just ##778 ).

I could do this for the other ## dials as well. Now, I can go to System Tools and tap on the icon to get into EPST.

[EDIT: Total Commander can create the shortcut as well, so no need to use File Explorer]

[EDIT 2: Won't work for DATA ##3282#, so I'm still looking for solutions -- I think I need to fix the dialer that came with the ROM]