You can use animated .GIFs as the uploaded image, however the animation will not be preserved. This is because, techincally, it's very tricky to merge two different types of animation, since properties such as the speed of animation and delay between each animation frame are usually different for each file.

You can now select from 4 different animation speeds. These apply to both video and animated GIF downloads.

In the animation tab, underneath "animation preview", you can change the "Speed" setting. Note that some web browsers may play animations at slightly different speeds. We recommend using the default "Normal" speed in most situations.

If you need more precise control over the animation speed, you may be able to do this using other software. For example, in Jasc Animation Shop (Windows), the process is as follows:

Load the .GIF file into Jasc Animation shop after first applying effects in Glitterboo.

Select all frames of the animation by pressing Edit->Select All.

You can now change the overall animation speed by going into Animation->Frame Properties and changing the "Display time" value. e.g. to 10. Use smaller values for a faster animation, and larger values for slower - you don't need to change this too much - for example if it's set to 7, changing to 10 will give a slower effect.

You can now save the modified animation file.

For video downloads, you should be able to change the video framerate in most video editors. This will change the overall animation speed.

Yes, Windows Movie Maker supports loading in animated .gif files as part of a movie.

You will need to adjust the timeline in moviemaker for each file, to set how long it plays for, otherwise it may just play for a default of 5 seconds.

First check that the timeline at the bottom is displayed by going to View and Timeline.
Then use "Import media" to load the .gif file, and add it to the timeline by dragging it there.

You can now adjust the playing time of the animation by dragging the duration slider on the timeline at the bottom.

More information is available here:
Microsoft Windows Movie Maker and animated gifs

If you're using a number of different photo editing tools, it's easiest to create the right sized image first, then add animation effects on glitterboo and download as "Original size" as the last step (up to 2048 pixels width/height for members).

This means that the image you download will be the same size as the one uploaded.

However, you can also resize animations with software such as Jasc Animation Shop 3 (Windows download). Load up Animation Shop, open the .gif file, then select "Animation" and "Resize Animation", and then "Save As" to save as a new file.

The animated GIF file format is limited to 256 colors for each image it displays. This is much less than other standard photo formats such as JPEG, which can use up to 16 million colors (however, these other file formats don't usually support animation).

As a result of this, if you have an especially large or colorful image in GIF format, the image quality may start to suffer as there are simply not enough colors available to display at a high quality.

This is typically more of a problem for photographs rather than graphics.

We recommend using video downloads for larger sized/higher resolution animations, since the video formats can reproduce all of the original color information with very little loss in image quality.

However, it is possible to achieve good quality animated GIFs with larger image sizes, if some care is taken in choosing source images that won't suffer very much from the restricted color palette.