> ok ,it worked...

Glad to hear it worked out OK.

> ... but now i still dont understand the use of
> the 'store link' button,

Consider the case where you've stumbled across a patch that you really
like, but it's already been set up with a split.

There's no easy way to tell which patch was originally used to form the
split so there's no easy way to 'tweak' the link patch. Similarly, if
you just wanted to use the 'split' sound, you might have to go through
all the patches to find which one it was.

Instead you can use commands like 'store link' to store just the link
portion of the patch somewhere (e.g., store unknown, nice sounding link
to Patch B7. Now you can modify B7 however you'd like to get it to
sound the way you like).