Just thought I'd share this, from Windows Vista 32-bit...
I can't stand having the \masm32 folder in the root of C:\
I also didn't want to change all the absolute path references in all the source files, MakeIt.BATs, etc.
So, after the installer finished I ran this script:
Move \Masm32 \Dev\Masm32
md \Masm32
cd \Masm32
MKLink /d bin \Dev\Masm32\bin
MKLink /d include \Dev\Masm32\include
MKLink /d help \Dev\Masm32\help
MKLink /d macros \Dev\Masm32\macros
MKLink /d lib \Dev\Masm32\lib
Using the symbolic links, everything seems to work just fine: Assemble+Link from inside QEditor and the MakeIt.BATs.
Under my Explorer pop-up context menu item, I add C:\Masm32\Bin to that console window's Path before running ML and Link.