Other reason is that live file is on a folder unlike in UNetBootIn files which are out in the open in the fat partition.
I wanted to cut and paste these files into the USB but tried a different method which did the trick.
For parted magic which was a zip file I had to cut and paste those files and that also did the trick but one has to have one Flash Drive prepared by downloading the full quota of files and kernels to copy later to another Pendrive.
When it asked whether to overwrite the files already there, I chose no to all, so that init and kernel files were not erased.
Menu file was also left intact.
I did this because PCLinux USB Creator install its image on a ext file partition and not on fat partition.
My BIOS does not read ext files at boot time which I tried several times. It is usual for the BIOS to read DOS files or GRUB and not other formats.
So I got PCLinux on FAT partition and it booted OK.
The down side was I could not boot DSL and that was the price I have to pay for fiddling with UNetBootIn.
The problem with UNetBootIn is when I copy it from my hard disk it omits two files.
I hope in its future version it will rectify this minor anomaly and verify before exiting that both uninit and unkernel are there for it to boot when an image is copied from the hard disk.
I have to do this to save time of the downloading of the Iso (I have all the Isos I downloaded over the last two years).
For the time being if you want it to boot do not skip or try shortcuts like what I did.
Longer method of course work but do not overwrite the files written on the first run.
I have tried to install from the downloaded (by UnetBootIn) temporary image but that time also the the two booting files were missing.
I have to pen this since part magic I am downloading takes a long time even though it is 156 MiB.