(Update: Once you solve your problem, you might want to use wperl instead of perl. ActivePerl's wperl is identical to their perl, except it doesn't open a console window. By using wperl, you won't see the console blink in and out. )

When I misread your problem, I thought you might have found the following batch file useful.

(Update: Corion just informed me that cd /d drive:\path does the same as the following. )

@echo off

if (%1)==() (
   cd
   goto Exit
)

if (%1)==(/?) goto Usage
if not (%2)==() goto Usage


for %%p in (%1) do (
   %%~dp
   cd "%%~fp"
)


goto Exit

:Usage
echo usage: %0 [ {rel_path} / {abs_path} ]
echo.
echo    Switches to current drive and the current dir to those
echo    of the supplied path.
echo.
echo    If no argument is supplied, displays the current dir.

:Exit
[download]

You can use it as follows:

mycd d:\
[download]

mycd "C:\Program Files"
[download]

# Start a shell in d:\
cmd /k mycd d:\
[download]

# Start a command in d:\
cmd /c mycd d:\ & mycommand args
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