Hang reproduced with civilization 1 version 475.01 and dos-box-x version 0.83.22 debugger:
// SECTION 1 DISASSEMBLY:
152A:00002F4E B80006 mov ax,0600
152A:00002F51 F72ECA64 imul word [64CA] ds:[64CA]=0004
152A:00002F55 8BD8 mov bx,ax
152A:00002F57 B80C00 mov ax,000C
152A:00002F5A F7AE48FF imul word [bp-00B8] ss:[FC2C]=0015
152A:00002F5E 8BF0 mov si,ax
152A:00002F60 8A80FE90 mov al,[bx+si-6F02] ds:[FFFF92A4]=287B
152A:00002F64 98 cbw
152A:00002F65 898648FF mov [bp-00B8],ax ss:[FC2C]=0015
152A:00002F69 8B861CFF mov ax,[bp-00E4] ss:[FC00]=0022
152A:00002F6D 398648FF cmp [bp-00B8],ax ss:[FC2C]=0015
152A:00002F71 7403 je 00002F76 ($+3) (no jmp)
152A:00002F73 E90600 jmp 00002F7C ($+6) (down)
152A:00002F76 C78648FFFFFF mov word [bp-00B8],FFFF ss:[FC2C]=002B
152A:00002F7C E93CFF jmp 00002EBB ($-c4) (up)
// SECTION 2:
152A:00002EBB 83BE48FFFF cmp word [bp-00B8],FFFF ss:[FC2C]=002B
152A:00002EC0 7503 jne 00002EC5 ($+3) (down)
152A:00002EC2 E9BA00 jmp 00002F7F ($+ba) (down)
152A:00002EC5 B80006 mov ax,0600
152A:00002EC8 F72ECA64 imul word [64CA] ds:[64CA]=0004
152A:00002ECC 8BD8 mov bx,ax
152A:00002ECE B80C00 mov ax,000C
152A:00002ED1 F7AE48FF imul word [bp-00B8] ss:[FC2C]=002B
152A:00002ED5 8BF0 mov si,ax
152A:00002ED7 B022 mov al,22
152A:00002ED9 F6A8F790 imul byte [bx+si-6F09] ds:[FFFFA9B7]=E90
152A:00002EDD 8BD8 mov bx,ax
152A:00002EDF 83BF3E1100 cmp word [bx+113E],0000 ds:[293E]=0045
152A:00002EE4 7F03 jg 00002EE9 ($+3) (down)
152A:00002EE6 E96500 jmp 00002F4E ($+65) (down)
152A:00002EE9 833E647000 cmp word [7064],0000 ds:[7064]=0000
152A:00002EEE 7F03 jg 00002EF3 ($+3) (down)
152A:00002EF0 E90400 jmp 00002EF7 ($+4) (down)
152A:00002EF3 FF0E6470 dec word [7064] ds:[7064]=0000
152A:00002EF7 8B4608 mov ax,[bp+08] ss:[FCEC]=FFFF
152A:00002EFA 99 cwd
152A:00002EFB 3D0100 cmp ax,0001
152A:00002EFE 7403 je 00002F03 ($+3) (down)
152A:00002F00 E94B00 jmp 00002F4E ($+4b) (down)
// SECTION 1 REGISTERS:
----Register Overview-----------------------------------------------------------
EAX=0000FFFF ESI=000000FC DS=323E ES=6177 FS=0000 GS=0000 SS=323E Real
EBX=000000AA EDI=000002D8 CS=152A EIP=00002F4E C0 Z0 S1 O0 A0 P0 D0 I1 T0
ECX=000000B2 EBP=0000FCE4 NOPG IOPL3 CPL0
EDX=0000FFFF ESP=0000FBD8 359
ST0=00000.00 ST1=00000.00 ST2=00000.00 ST3=00000.00
ST4=00000.00 ST5=00000.00 ST6=00000.00 ST7=00000.00
// SECTION 2 REGISTERS:
----Register Overview-----------------------------------------------------------
EAX=00000022 ESI=00000084 DS=323E ES=6177 FS=0000 GS=0000 SS=323E Real
EBX=00001800 EDI=000002D8 CS=152A EIP=00002EBB C0 Z0 S0 O0 A0 P1 D0 I1 T0
ECX=000000B2 EBP=0000FCE4 NOPG IOPL3 CPL0
EDX=00000000 ESP=0000FBD8 548
ST0=00000.00 ST1=00000.00 ST2=00000.00 ST3=00000.00
ST4=00000.00 ST5=00000.00 ST6=00000.00 ST7=00000.00