Image not centered and sometimes multiple images appear at the same time.

The images I'm using are large and vary quite a bit in dimensions.
Anki Version 2.1.15 (442df9d6)
Windows 10

[lovac42]

Each themes folder contains a settings.json file that you can offset the center point and timing. But they should be within 20% of each other in size to prevent positioning issues.

To prevent errors, image FX files size (in kb, not dimention) should be kept small to prevent loading issues on 2.1. You probably have extreme large images of high quality that caused this. It won't be an issue on 2.0, but 2.1 is sensitive.

[CoffeeDrinkRabbit]

I had encountered the same problem, but I noticed that the starting and ending pictures didn't seem to have the same position deviation as the middle space pictures

[lovac42]

I suppose the template/javascript/css could have something to do with that. 2.1's toolkit has a bug that can't display images, so I had to embed the image into the review card. Depending on the template, the size could be screwed. Hopefully the next update to the toolkit would have fixed this issue, and I could then use the same method I used on 2.0 to display the images without interference from the template.

So I followed your instructions and compressed and resized the images and the problem, for me at least is solved. Thanks.
Sorry for the late reply btw.