Had a tiny bit more progress on the zoom, managed to dump the firmware, and now I've been able to distinguish the header and checksums, all the info will be documented in a wiki once working.
Also another ebay bargin an Edimax NS-1500N, this listed on their site as a wireless NAS but has an RT3050.
This thing is tiny! its like 1/2 the size of the zoom. its listed as having 4MB flash on the edimax site but Amazingly it seems to have 8MB of flash inside :O so I'll be moving focus to that.