How do I open a file using the GetOpenFileName function in ASM?

Question

The following task is on the agenda: "Use the GetOpenFileName function to select a file. Check if the file is less than 3 days old, execute it. Otherwise, display a dialog box asking about deleting the file. If the user is useful, wipe it." (Attention. If the task says to use a structure, then it must be placed in dynamically allocated memory)

After successful execution of the GetOpenFileName function, I want to open the selected file. I tried two options:

1. Through the CreateFile function (with the parameters necessary only for opening and reading the file)
2. Through the OpenFile function

I refused OpenFile as it is obsolete. I figured out a little with CreateFile, but for some reason the eax register is filled with FFFFFFFF, and the debugger writes: "Syntax error in the file name, folder name or volume label," although the idea should not be(((

And if I just leave [edi].lpstrFile, then eax 0000057C

File.inc

include WINDOWS.inc

include user32.inc
include kernel32.inc
include comdlg32.inc

includelib user32.lib
includelib kernel32.lib
includelib comdlg32.lib

.data

  Time_title    db ' Lab_3',0
  buf db 255 dup(0)

File.asm

.386
.model flat,STDCALL
option casemap :none  ;case sensitive
include Third.inc
include RADbg.inc

Mem_Alloc PROC Buf_Size:DWORD
  add Buf_Size,4
  invoke GlobalAlloc,GMEM_MOVEABLE or GMEM_ZEROINIT,Buf_Size
  push eax
  invoke GlobalLock,eax
  pop [eax]
  add eax,4
  ret
Mem_Alloc endp

Mem_Free PROC DATA:DWORD
  mov eax,DATA

  sub eax,4
  mov eax,[eax]
  push eax
  push eax
  call GlobalUnlock 
  call GlobalFree   
  ret
Mem_Free endp


.code
Begin:
  call main
  invoke ExitProcess,NULL

main proc
  LOCAL hFile:DWORD
  LOCAL ftCreate, ftLocale: FILETIME;
  LOCAL stUTC, stLocal: SYSTEMTIME;

  invoke Mem_Alloc, sizeof OPENFILENAME
  mov edi, eax
  assume edi: ptr OPENFILENAME
  xor eax, eax
  mov [edi].lStructSize, sizeof OPENFILENAME
  mov [edi].lpstrFile, offset buf
  mov [edi].nMaxFile, 255
  invoke GetOpenFileName, edi
  invoke CreateFile, addr [edi].lpstrFile, GENERIC_READ,\   ;немного разобрался
    FILE_SHARE_READ, NULL, OPEN_EXISTING,\
    FILE_ATTRIBUTE_NORMAL, NULL
  mov hFile,eax
  invoke GetFileTime, hFile, addr ftCreate, NULL, NULL
  invoke FileTimeToLocalFileTime, addr ftCreate, addr ftLocale
  invoke FileTimeToSystemTime, addr ftCreate, addr stUTC

  jne l1

  jmp l2

  assume edi: dword
  invoke Mem_Free, hFile
l1:

l2:

  ret

main endp   
end Begin