Currently the properties dialog for the table of figures doesn't provide the
same possibilities as the one for the table of content. It's not possible to
insert a tabstop inside the reference text for the pictures. This leads to
misaligned numbers if the numbering steps up one digit. 

Here is an example (taken from the german version):

...
Abb. 9: ninth picture...........xy
Abb. 10: tenth picture..........xy
... 

It would look better like this:

...
Abb.  9: ninth picture...........xy
Abb. 10: tenth picture...........xy
...

or this

...
Abb. 9    ninth picture...........xy
Abb. 10   tenth picture...........xy
...

There is a workaround if you change the indention for the paragraph style that
is assigned to the table of figures and then do a search for "Abb. [:digit:]:
|Abb. [:digit:][:digit:]: " in my case and replace with "&\t". But this has to
be done after each update of the table.

I shall not forget to thank you for this great Office Suite!
It offers fantastic possibilities!

Hendrik