So just to make sure we are talking about the same thing:
The original post author was trying to redistribute static's and that was generating AS-External-LSA's.
You're noting that an OSPFv3 process doesn't advertise an area range into another area unless the area generating the summary has at least 1 active neighbor. I can confirm this behavior in 6.40rc24. It also doesn't seem to be restricted by the OSPFv3 RFC so I'm going to go out on a limb and say this is a bug. Especially since OSPFv2 supports this behavior.
Speculation: The inter-area prefix LSA is only being generated when network LSAs are being calculated? You can see them in GNS3 immediately after a neighborship is formed. LS Updates go out into the other areas from the ASBR and naturally the summary shows up.
MikroTik forum ops, can we get a nod on this or do we need to send this to email@example.com