Hi Roland;
This is completely incorrect ..... you must never use a 32 bit version of GS on a 64 bit version of the MS-Windows O/S!!!!!! 
1) Download and install GS 8.71 64 bit version.
2) Install GS 8.71 and make sure that you set the GS_DLL environment variable ...
ie: GS_DLL=C:\Program Files\GS\gs8.71\bin
3) Install the "Sybase DataWindow PS" printer from the GS 8.71 64 bit .INF file located in the GS install's LIB sub-folder
4) Optional: Add the GS BIN folder to your system path
5) Reboot your PC.
Now, PDF support should be working in PB 10 and higher on your 64 bit MS-Windows machines.
Note: v8.71 of GS has some key fonts that are not included in later releases of GS and these fonts are also no longer included with newer MS-Windows versions either. So what ever you do ... never delete GS 8.71 from your machine.
You can now upgrade GS as follows:
a) Download and install the latest GS version 9.x or higher 64 bit version
Do not uninstall GS 8.71
b) Install GS 9.x and make sure that you set the GS_DLL environment variable ...
ie: GS_DLL=C:\Program Files\GS\gs9.01\bin (for example)
c) Delete the old "Sybase DataWindow PS" printer definition
d) Install a new "Sybase DataWindow PS" printer from the GS 9.x 64 bit .INF file located in the GS install's LIB sub-folder.
e) Optional: replace the GS 8.71 BIN folder in your system path with the GS 9.x BIN location.
f) Reboot your PC.
FWIW: This procedure works for me and all my clients every time! Tested with PB 10.5 through all versions to PB 12.5.2
HTH
Regards ... Chris