You’re right. Looking at the manual for version 4, it’s a completely different program than 5! They made some huge improvements in friendliness for the new one.
This said… I’m looking at a screenshot of the interface. You’ve got your menu bar. Below that, a row of icons. Below that, two fields (“Image Title” and “How to Remove”). Look just below that.
From left to right, you’ve got the height and width with offset options, you’ve got checkboxes for interlacing and transparency, and on the far-right of that section, you’ve got a box labeled “Delay: (1/100th of a Second)”.
That’s hopefully it. The manual’s pretty vague on this one, but their glossary defines Delay as “the duration that the image layer is displayed before being removed and replaced by another”.
I don’t see how you can select every frame to affect them at once, so you may have to change that value one frame at a time.
The blue guy is probably better for you to study, because of the pauses - you know the delay value should change several times throughout the file, so you can get a sense of relative scale from that.