Quoting @Theklan from T197588#5731306:
I have tried to to this using this Wikibase instance: https://arbaso.wiki.opencura.com/. I find a problem following the instructions here (https://github.com/wetneb/openrefine-wikibase) with Redis. It seems that there is an error with INCRBYFLOAT.
redis.exceptions.ResponseError: unknown command 'INCRBYFLOAT'
But it could be my own problem!
Which version of redis are you running?