At the present time, iScreensaver Designer 5.2 provides support for macOS 10.13 High Sierra, but there are some functional limitations.
Please read the 10.13 High Sierra Tech Note
as well as the Release Notes
Due to changes made by Apple, iScreensaver Designer version 5.2 does not currently support macOS 10.14 Mojave.
Please read our forum post
for the latest updates.
[Solved] Can't get a long SWF screensaver to loop
I just started using this software to build a corporate screensaver using Animate CC 2018. Currently, the SWF is around 53 seconds long and set to loop forever. However, it will not loop. I have made test SWF files that are shorter that loop perfectly. Is there a limit to how long a file can be and still loop or should I just split the file into smaller files and have the whole project loop forever?