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Если я правильно логику понял:

Код:

@echo off

set "d=C:\Doc\"
set "f=Fora.vek"
set "f1=1Fora.vek"
set "app=Zorro.exe"

pushd "%d%" & call:size "%f%"

:size
if %~z1 equ 95800 (
   ren %1 "2%~1"
   ren "%f1%" %1
   ping -n 51 127.0.0.1>nul
   ren %1 "%f1%"
   ren "2%~1" %1
   exit
) else (
   if %~z1 equ 805132 (start /wait "" %app% & ren %1 "2%~1" & ren "%f1%" %1)
   exit
)