1h50m is enough to transfer in Madrid Airport?

This is a difficult decision. Assuming this is booked as a single ticket, than 2 hours should be plenty, if the incoming flight is on time.

However, there are things to consider:

1. Nothing is every 100% guaranteed. There is always a non-zero chance, that you miss your flight and you need to assess the consequences and figure out how much risk you want to take
2. If you miss a flight, Air Europa will need to book you the next available flight for free, but this may very well be only the next day.
3. You need to find out, what would happen to your cruise? Can you join later at the first port? Would Air Europa willing to get you there ?
4. You also need to asses the chances of being late. Air Europa is a budget carrier with less than stellar reviews. The OPO->MAD flight has on on time performance of 85% and in 5% of cases it's excessively late (See https://www.flightstats.com/v2/flight-ontime-performance-rating/UX/1146/OPO)
5. If you first flight is delayed, you may still make it, but your bags may not. In this case, Air Europa would deliver the bags later, but in order to do this, you need to give them an address, which is difficult for a cruise.

So overall you have a very good chance of making this connection, but also a non-trivial chance that you don't. This may have serious consequences for your (probably expensive) cruise, so maybe it's worth spending a few more dollars on the flight to get a safe connection.

You can also look into travel insurance to cover the financial risk, but you have to make sure that it would actually cover this case with enough funds.

Will you be able to meet the start of the cruise if you miss your flight connection and need to take the next available one? That might well be 24 or even 48 hours later.

I would not risk a short connection unless there was a long time between arrival in Miami and the start of the cruise. I would rather spend 6 hours in transit than miss the cruise, and even then I would like to arrive and stay in Miami for a while before setting off on the cruise, so I would not have to worry about a flight delay spoiling the cruise.

If you are travelling with baggage in the baggage hold then you need to make sure that it is checked for your Miami at your initial departure airport. If you are travelling with hand luggage then you are fine. If your baggage is checked for Madrid you need to drop off your bag again.

If you have boarding passes printed for both flights and checked in already you won't need to do it again.

The bus goes every 5 minutes and takes 5 minutes. Customs and immigration should take around 30.

Time:

• Customs and immigration 30 minutes
• Bus and entering the terminal 15 minutes
• Getting through security 20 minutes
• Check-in (if you haven't already) 20 minutes

Personally, I think it is doable. Try to check-in for both flights and check your luggage to Miami.

To walk from Terminal 2 to 1 will take around 7 minutes. It depends what gate you go from and come to.