If you read my response carefully, you'll see I said 2G for the EXE
I did read it correctly. You said:
Since PB 12.5.x is 32bit - the Blob upper limit is 2G.
You also say:
Newer 64 bit O/S versions will give you the 4G space when running a 32bit application using WOW.
Once again, that's only if the LARGEADDRESSAWARE flag is set. If it isn't, a 32 bit application is still limited to 2GB, and by default the flag is not set:
https://msdn.microsoft.com/en-us/library/windows/desktop/aa366778(v=vs.85).aspx#memory_limits
| Memory type | Limit on X86 | Limit in 64-bit Windows |
|---|---|---|
User-mode virtual address space for each 32-bit process | 2 GB Up to 3 GB withIMAGE_FILE_LARGE_ADDRESS_AWARE and 4GT | 2 GB withIMAGE_FILE_LARGE_ADDRESS_AWAREcleared (default) 4 GB withIMAGE_FILE_LARGE_ADDRESS_AWAREset |