Increase the number of screenshots / time of the replay
The number of screenshots seems to be memory constrained such that larger desktops (higher resolution) and multiple monitors have few screenshots compared to smaller desktops with a single monitor. One of my clients has works in design and has two high resolution monitors. The ticket shows 12 screenshots while my machine records 20 screenshots. Please make this configurable. Maybe store a minimum number of screenshots up to a maximum amount of memory.
You are correct about the resolution affecting the number of slides the viewer can hold, this is unfortunately actually a function of the maximum size sprite that Chrome supports. We do have a plan for increasing this in the future and it is on our roadmap already. It requires a good bit of fairly complicated math but it should be done before release.
We have reworked and rewritten this from scratch. An added bonus of changing the process is that the entire replay is now downloadable as an html file. It embeds the image, the annotations, and the player in the file so it can be distributed and viewed on any machine with chrome without additional software.