By using an old profile with a new version of K-Meleon you might miss some of the new features. Compare your profile files with those available in C:\Program Files\K-Meleon\defaults\profile\ and do the needed adjustments.
For migrating from K-Meleon 0.7 to K-Meleon 0.8 these new features include LButton, MButton and RButton in accel.cfg, and DocumentImagePopup and FrameDocumentImagePopup in menus.cfg.
Backup your old K-Meleon profile
The profile files are normally located in:
C:\Program Files\K-Meleon\Profiles\[your name]\!!!!!!!!.slt
The following files can be backed up to tranfer your profile to a new install of K-Meleon. Do not try to transfer any other files. (and never mind if your profile doesn't have all of these files)
Installing your new K-Meleon