PMKEY v0.5 includes DOS Box support. Just load keytsr
    program in Dos Box.

    KEYTSR works just like PMKEY, hotkeys ALT+0 -> ALT+9, CTRL+0 ->
    CTRL+9. Use left shift if you want to pass hotkey into your Dos
    Program.

    If KEYTSR doesn't work with your favorite Dos program only thing
    that i can say is "I'm sorry". I don't have time, and to be
    honest, i don't have interest for Dos Box support. I don't know
    much of TSR coding so don't expect much from KEYTSR, few people
    have requested it that's why i coded KEYTSR. Personally i think
    DOS should die, it's just so crappy operating system.

    Making working TSR is hard... Because DOS is single task operating
    system two DOS program cannot call DOS API functions at the same
    time, and Microsoft documentation sucks badly when it comes to TSR
    programming. You have to use all kind tricks to make TSR program
    work, so i'm sure that KEYTSR will not work with every program,
    but what i tested it seemed to work very well.

    KEYTSR uses undocumented dos interrupt 034h, it gives address to
    DOS BUSY FLAG, if BUSY FLAG is non-zero KeyTsr won't make popup,
    what this means is sometimes KEYTSR doesn't seem to be working
    all right. For example if you try to press hotkey button while
    dos program is writing to disk KEYTSR will just ignore your
    keypress.

    Anyway, KEYTSR works without any problems in my machine,
    and with programs that i use. So have fun...