i chose this extension because it's the only one i found to use kenburns without flash.
Sadly, like i noticed nearly a month ago already, the kenburns is almost impossible to use as it is so much ressource hungry.
may it be on firefox or chrome, on a brand new site, so not bloated, it uses between 30 and 50% of my cpu on a clean, new computer. (dual core 8 gig ram)
and on older computers, it uses almost 100% of cpu.
so for kenburns effects, there's no way to use it at all (i found none actually)
As explained in reply to a similar comment below, most dynamic features including the Ken Burns effect are part of third-party code built into showplus and not showplus itself. Even while the developer has already gone a long way in improving the third-party code, the best solution would be to replace it entirely. My opinion, even if biased, is that showplus is a great Joomla extension despite a few limitations, especially in the light that it is completely free. "Below average" ratings are certainly not sending a positive message to the developer to spend time and effort on improving the software; on the contrary, they cast a shadow on 95% of the other features that work as intended with absolutely normal resource consumption. Also, do not forget that dynamically rescaling an image (e.g. as part of the Ken Burns effect) is an expensive operation and will likely never fall into the same category as a simple fade or cut effect.