Open Stack in same folder -- relative path?

[Sivakatirswami]

I have two stacks in one folder

1) Guestbook_engine.rev
2) Guestbook Records.rev

in the same folder

I though that  a button in stack 1)

on mouseUp
   go stack "Guestbook Records.rev"
   toplevel "Guestbook Records"
end mouseUp

should work to open the "adjacent" stack 2)

but it doesn't

what am I missing?

I need this to be portable.

Sivakatirswami