Lets see a tutorial, howto install skin to V8 easily without any firmware hack.
Connect phone to PC in memory card mode.
Navigate to unKnown folder, Create hore your Skin forder and put skin(s) here:

Now switch phone back to modem mode, and connect P2kCommander5
and read filelist:

Navigate here:

Download User_1.chm
And open it with some texteditor (pic shows notepad.exe)
Warning: linux text files contains only LF at line end. Windows text files has both CR and LF. Thats why file content loook strange. Pay attention to make this line ends untouched while editing. Edit only letter characters. Or use some smarter texteditor (like ultraedit)
To make our new skin installed we must edit this file:
First search this like "Skin =" This entry now target a folder in CG52 which is readonly:

Change this to target our skin folder in mystuff:

Also search theme name and edit it:

Then save this edited file as a new name User_2.chm: (or the higher existing number+1)

Upload this chm file:

Finished , now i can use this new skin even without restarting my V8.