I had to make the following changes to the original (*.for) files:

Because I had no f77 Compiler, but only a conversion programm f2c which
converts .f Fortan files to C (I used SAS/C 6.51) (If there is anyone
out there with a real f77 compiler for Amiga, try to compile the *.for
directly, the binaries should probably be smaller than mine).
First I had to remove all $ from the files (not included in the diff).
I had to rename some variables (all changed begin with 'my') and finally
I found out that f2c has one problem: It can't convert ascii to integer
(and via versa) automatically as the f77 compiler can. This problem only
occured in the pmtexb.f file. I used a dummy function (I don't know if there
exists a ascii to integer function in Fortran, if you know mail me please!)
ord and replaced it in the c file through atol. (Details see diff file below).
So if you want to recompile it, either use the pmtexb.c file or use a real
Fortran compiler.

diffs between pmtexb.f and pmtexb.for:
322c322
<       subroutine getchar(line,iccount,mychar)
---
>       subroutine getchar(line,iccount,char)
329c329
<       character*1 mychar,s
---
>       character*1 char,s 
338c338
<       mychar = line(iccount:iccount)
---
>       char = line(iccount:iccount)
595c595
<       subroutine notex(mynotex,lnote)
---
>       subroutine notex(notex,lnote)
600c600
<       character*25 mynotex
---
>       character*25 notex
623c623
<               mynotex =s//'ccc'//ud//' '//note
---
>               notex =s//'ccc'//ud//' '//note
626c626
<               mynotex =s//'cc'//ud//' '//note
---
>               notex =s//'cc'//ud//' '//note
629c629
<               mynotex =s//'c'//ud//' '//note
---
>               notex =s//'c'//ud//' '//note
631c631
<               mynotex =s//'q'//ud//' '//note
---
>               notex =s//'q'//ud//' '//note
633c633
<               mynotex =s//'h'//ud//' '//note
---
>               notex =s//'h'//ud//' '//note
635c635
<               mynotex =s//'wh'//' '//note
---
>               notex =s//'wh'//' '//note
640c640
<               mynotex =s//'c'//ud//'p'//' '//note
---
>               notex =s//'c'//ud//'p'//' '//note
642c642
<               mynotex =s//'q'//ud//'p'//' '//note
---
>               notex =s//'q'//ud//'p'//' '//note
644c644
<               mynotex =s//'h'//ud//'p'//' '//note
---
>               notex =s//'h'//ud//'p'//' '//note
646c646
<               mynotex =s//'c'//ud//'p'//' '//note
---
>               notex =s//'c'//ud//'p'//' '//note
659c659
<             mynotex = s//'sk'
---
>             notex = s//'sk'
661c661
<             mynotex = s//'rlap{'//s//'qsk'//s//'pause}'
---
>             notex = s//'rlap{'//s//'qsk'//s//'pause}'
667c667
<             mynotex = s//'ask'
---
>             notex = s//'ask'
670c670
<             mynotex =s//'hs'
---
>             notex =s//'hs'
672c672
<             mynotex =s//'qs'
---
>             notex =s//'qs'
674c674
<             mynotex =s//'ds'
---
>             notex =s//'ds'
676c676
<             mynotex =s//'qp'
---
>             notex =s//'qp'
678c678
<             mynotex =s//'hpause'
---
>             notex =s//'hpause'
681c681
<             mynotex =s//'pause'
---
>             notex =s//'pause'
808c808
<       character*25 mynotex
---
>       character*25 notex
1091,1092c1091,1092
<               call beamstrt(mynotex,lnote,nornb,ihornb)
<               call addstr(mynotex,lnote,sout,lsout)
---
>               call beamstrt(notex,lnote,nornb,ihornb)
>               call addstr(notex,lnote,sout,lsout)
1110c1110
<                 mynotex = s//'pince '
---
>                 notex = s//'pince '
1113c1113
<                 mynotex=s//'mordant '
---
>                 notex=s//'mordant '
1116c1116
<                 mynotex=s//'mtr '
---
>                 notex=s//'mtr '
1119c1119
<               call addstr(mynotex(1:lnote-1)//notef(ihorn),lnote,
---
>               call addstr(notex(1:lnote-1)//notef(ihorn),lnote,
1124c1124
<               call beamn1(mynotex,lnote)
---
>               call beamn1(notex,lnote)
1129c1129
<               call beamend(mynotex,lnote)
---
>               call beamend(notex,lnote)
1135c1135
<               call beamid(mynotex,lnote)
---
>               call beamid(notex,lnote)
1138c1138
<               call notex(mynotex,lnote)
---
>               call notex(notex,lnote)
1140c1140
<             call addstr(mynotex,lnote,sout,lsout)
---
>             call addstr(notex,lnote,sout,lsout)
1215d1214
<       integer tof,tofa
1219,1220c1218,1219
<         nof = '0'
<         nofa = '-1'
---
>         nof = 0
>         nofa = -1
1230,1235c1229,1232
<         tof = ord(nof)
<         nof = char(tof+48)
<         if (tof .gt. 9) then
<          lnof = 2
<          tof = ord(nof)
<          nof = '1'//char(tof-10+48)
---
>         nof = char(nof+48)
>         if (nof .gt. 9) then
>           lnof = 2
>           nof = '1'//char(nof-10+48)
1237,1238c1234
<         tofa=ord(nofa)
<         if (tofa .eq.-1) then
---
>         if (nofa .eq.-1) then
1241c1237
<         else if (tofa .lt. 10) then
---
>         else if (nofa .lt. 10) then
1243c1239
<           nofa = char(tofa+48)
---
>           nofa = char(nofa+48)
1246c1242
<           nofa = '1'//char(tofa+38)
---
>           nofa = '1'//char(nofa+38)
1298,1303c1294,1295
<         tof = ord(nof)
<         tof = tof+4
<         nof = char(tof+48)
<         tofa = ord(nofa)
<         tofa = tofa+4  
<         nofa = char(tofa+48)
---
>         nof = nof+4
>         nofa = nofa+4