@argii Glad to hear that the Moslo utility worked for you.
MS-DOS uses a 8.3 file name convention so, as @edmaul69 explained, will shorten long names. I would suggest using the TAB key to auto complete file names. In your example, you can type PTO (I usually type the first three characters) at the DOS prompt, hit TAB, then the the file name will auto complete to PTOMB1.EXE. If you hit TAB again, then DOS will cycle through other possibilities, PTOMB2.EXE, PTOMB3.EXE and so on. This also works on the Linux command line. For example, if you want to launch Emulationstation from the terminal, you can type emu, hit TAB, then command will auto complete to emulationstation.