Hi
I think it is ok now, to point to the OOo site for things.
I agree it is better to point to LO sites where possible but we can be fairly confident in OOo Extensions working equally well in LO. Also when Oracle were running the OOo websites they kept dropping out from time-to-time. Now that Apache are running them they seem to be up all the time and we can be reasonably confident that they wont suddenly vanish over-night.
The LO pages for Extensions are likely to continue to be more stable for LO than for Apache because LO has already done it's re-organising and Apache might still shift things around a bit to stream-line them a bit.
Regards from
Tom