This works okay on my old DOS machine but not on DOSbox 0.74, any ideas why?

Input
=====
ExIVP.1 !* 4, 6, 1, 0,
Y'* Y'' = 2 ! where Y(0) = 1 & Y'(0) = 2
2 ! Order of ODE
6 ! No. of Operations
8 3 0 1 7 19 ! Operator IDs
3 ! No. of Terms
-1 -2 11 ! Term IDs
ooo

Output
======
¯ Line 1
¯ Line 2

Your differential equation ...
<-- no Equation ... eqn should = "Y'* Y'' = 2"
¯ Line 3
************ stalls here on DOSbox 0.74 ... works okay on old DOS machine!

Source
======
open( 22, Status='scratch')
ooo
C in #1 ! file name
line = 0
line = line + 1 : write(L,11) '¯ Line ', line
call readLine( aline)
lastFile = aline
j = index( lastFile, "*")
lastFile = charnb( lastFile( 1: j-4))
j = index( lastFile, char(9))
lastFile = charnb( lastFile( 1: j-1))

C in #2 ! Equation
line = line + 1 : write(L,11) '¯ Line ', line
call readLine( aline): eqn = aline
write(L,14) ' ', ' Your differential equation ...'
write(L,14) eqn
C in #3 ! ORDER of ODE
line = line + 1 : write(L,11) '¯ Line ', line
call readLine( aline)
read(22, *) n8order <-- 1st read '22'!!! ... stalls here or near by
print *, n8order, aline
C in #4 ! NOPS
line = line + 1 : write(L,11) '¯ Line ', line
call readLine( aline)
read(22, *) Nops
print *, Nops, aline
ooo
procedure readLine( aline)
include 'ODEcalc.inc'
character aline*(*)
read(*,'(a80)') aline
j = index( aline, "!")
aline = aline( 1: j-1)
rewind 22
write(22,'(a80)') aline
rewind 22
end
======================

Thanks, Phil