Sorry to disappoint you, but why waste money and effort on a Zorro II RAM card that'll slow down the A4k considerably? Especially when it uses zips which are hard to get and expensive ($10-$40 per 2 MB)?
Instead you might want to consider either a Zorro III card (pricey and rare) or - better - a CPU card with RAM extension, you can get the RAMs for (next to) nothing then.
If you do want to continue the path: the missing socket must be a - well, missing socket. It doesn't make sense to leave it out as sets of 4 zips are required to form a bank (each zip is 4 bits wide and 4 zips in parallel are 16 bits wide).
The JP3:TEST setting disable the automatic addition of the card to the memory pool, ideal for testing.
