Do not download a "Lightroom portable 32 bits" file from an untrusted website. You are almost guaranteed to infect your computer with malware.
Inside the portable folder, locate the LightroomPortable.ini (or the .reg registration file). Add these lines if available: lightroom portable 32 bits
If you see a file labeled "Adobe Lightroom Portable 32-bit" online, it is almost certainly a repacked version of (released between 2010 and 2015). Do not download a "Lightroom portable 32 bits"
A typical cracked/thinapped Lightroom 5.7 portable includes: and often faster.
If the hunt for a safe portable version frustrates you, consider these native 32-bit portable alternatives. They are free, legal, and often faster.