Descriptive Problem Summary:
When you blend an animated sprite with another sprite, the animation is forced into a frame delay of 1 for every frame regardless of previous configuration.

Numbered Steps to Reproduce Problem:
Testcase: https://www.dropbox.com/s/dikugws4y0ocl27/ IconAnimationEditTestcase.zip?dl=1
- Compile and run the testcase project
- Activate the client verb
- Compare the animation speed to what's configured in the dmi

Expected Results:
A slowly pulsing box with a delay of 10

Actual Results:
A quickly pulsing box with a delay of 1

Does the problem occur:
Every time? Or how often? Yes
In other games? Tested both in sample case and ss13
In other user accounts? Yes
On other computers? Yes

When does the problem NOT occur? Never

Did the problem NOT occur in any earlier versions? If so, what was the last version that worked?
I'm unsure how far back this goes, at the very least it was an issue in 512 stable and I only now got around to making an example case for this report.

Workarounds:
Use only 1 delay frames and add a bunch of repeat frames. Though this is a very poor workaround in my particular case as it is more expensive to modify sprites with multiple frames like this.