Old K-Meleon portable versions:
Pocket K-Meleon 1.1.3 by JujuLand? (based in old Pocket K-Meleon by Douglas McFadzean).
K-Meleon Portable 1.5.0 by Travis Carrico.
I don't think that a K-Meleon 1.5 Portable version is needed.
You can convert standard K-Meleon 1.5.x in portable easilly.
1) Download 7z file (K-Meleon without installer), and 7z localization package if you like it.
2) Unzip 7z files in your USB memory.
3) Download or copy from your computer the needed libraries (msvcp71.dll, msvcr71.dll) to your K-Meleon folder in your USB memory.
4) Create a "profile.ini" file in USB memory K-Meleon folder.
5) Now start K-Meleon from USB memory only and config; Cache, History, Cookies.
In cache, uncheck "cache files on disk" option, and set "cache files in memory" to 20 or 30 MB, optional: you can uncheck also "cache website icons on disk" option.
In history, set "Keep a list of all pages visited..." option to 0 (zero) days.
Set others privacy options as cookies and remember login data as you like it.