You might want to try modifying the autoexec.nt and/or config.nt files in the %systemroot%\System32 directory... the config.nt file at least, possibly increasing the file handles from files=40 to files=100. Something along the lines of...
EMM = B=4000 RAM
dos=high, umb
device=%SystemRoot%\system32\himem.sys
files=100
...and in autoexec.nt have:
REM Install DPMI support
LH %SystemRoot%\system32\dosx
...with other LH lines REM'ed out, and then any SET or PATH lines that may already be present at the end. This should give about 612K for a program, run from a shortcut made to its .exe file. Right click the shortcut, and select "Properties" | On the "Memory" page, you can set an explicit value (rather than "Auto") for any EMM or XMS memory it may need, and for initial environment space.