I cant sync up the old classic wallets.
(...)
I tried the new research client and it works and syncs up correctly.
This gives a really useful info for me

havn't seen that there're 3 repos:
https://github.com/gridcoin/Gridcoin-masterhttps://github.com/gridcoin/Gridcoin-Researchhttps://github.com/gridcoin/Gridcoin-stakeGridcoin-Research connects and gets synced (there was a minor bug in clientmodel.cpp but I've fixed it and built the wallet. If anybody would like to use it, the wallet for 32bit Debians like Ubuntu, Mint etc could be downloaded from here
http://share.mukor.net/wallets/ and 64bit version will be later).
I've been trying with Gridcoin-master before. This was the cause of problem?
Which of them should I use if I want the Proof of Research only? Gridcoin-Research? Should it be always open like during staking?
When placing a deposit address (generated on Poloniex) into the wallet - I'm receiving a message, that it's not a valid GRC address... What's up?