Tested with fresh 6.2 EE SP11.
When you click on an image in Media Gallery, the carousel is shown.
Expected behavior: It is possible to browse through all images.
Real behavior: It is only possible to browse through the first 20 images
Steps to reproduce:
Add e.g. 21 images to document library root folder
Add media gallery portlet to a page
Click an image.
Click right button till you reach image 20
Right button disappears, image 21 cannot be viewed.
Note: Increasing pagination size allows to browse through 75 images at once. Slightly improves things (with the caveat that more space is needed by media gallery since more thumbnails are shown) but we have folders here with more 250 images and more.