Air Europa system not recognising Alitalia Elite Plus status
I had a pretty mixed experience with UX as a DL Platinum (SkyTeam Elite+) on a business class ticket.
IIRC, you may be able to find your UX reservation via the KLM or AF websites, but I don't know if a seat selection there is possible or would stick. UX's website and internal systems seemed pretty bad...even their airport agents were having trouble getting anything status-related to happen.
Good luck!