Can you post a picture of your top entrance?
here you go, unpainted batch me and the grandson just finished last week. Might also note I use screened bottom boards with them.
My brother and I made entrances just like those pictured back in the 1960's, it was then I stubbled upon ventilation problems as they exist in a langstroth hive.
The 3 hive we put those types of entrances on developed the following problems:
1. The standard brood area was abandoned and moved up above the "new entrance."
2. The abandoned area quickly became moldy and foul smelling and if we'd of had SHB in those days it would have been infested.
3. Every hive developed Nosema and chalk brood from the rampant dampness within the hive.
4. The moisture was so bad that the bottom boards warped and buckled.
5. I lost 2 of the 3 hives set up that way due to moisture and disease.
With all that said the system has since been made to work:
1. Vents at the very top of the hive, any vent lower than the top bars of the top super still allows moisture to build up.
2. Screen bottom boards, the vents need to create a chimney so the bees can be more efficient by directing their airconditioning in one direction. The normal action of the bees forcing air up onside of the hive and down the other side doesn't work on the boxes below the new entrance because of the large additional entrance and solid bottom board. Essentially without a top and bottom vent the introduction of the upper entrance created a serious ventilation/stagnant air pocket within the hive which was abandoned.
3. Queen excluer, if the hive becomes too drafty with such a large upper entrance the brood chamber will get chilled and the queen will move up. Adequate ventilation should preclude this but the excluder will help in keeping the queen down.