I checked the official requirements for the PE-DESIGN application and it appears that it supports 64bit architecture mode:
Operating system Windows Vista, Windows 7, 8, 8.1 (32 or 64 bit)
Processor 1 GHz or more
Memory 512 MB (1 GB or more is recommended.)
Hard disk free space 300 MB
Monitor XGA (1024 × 768), 16-bit color or higher
Device Mouse
As you can see above, it's mentioned that you can install it on 64bit. However, latest version is required for this to work.