Hello;

- From the perspective of the peer/ca/orderer etc that are written in Go, I know that others have managed to recompile for ARM. Understand it's possible, but not sure how the performance is though.. though I believe the Pi4 probably has the processor power esp, if an external drive is used rather than SD storage.

- The docker image you mention is from one of those that I know has done the build; normally the prereqs don't need building - so I can't really give you any pointers there I'm afraid. 

- In terms of compatibility I refer you to https://github.com/hyperledger/fabric-chaincode-java/blob/master/COMPATIBILITY.md 

Briefly:
- There is the wire protocol between peer and chaincode. This is compatible across versions... 1.4 peer can talk to a 2.2 chaincode vice/versa subject to the request function actually being there.
- For running the chaincodes, the peer will spin up a docker container - this will have a certain runtime (java/node etc) within it.  Can this support the version of library you want to run?
- The docker images come with a pre-cached version of the language libraries; you can override these should you wish. 


- Last thought;; personally if possible I'd used the Nodejs v2.x contract API - it has no native dependencies and is pure JS code. It should be easier to run.

Matthew