Shape animation issues

I'm inserting shapes, just by going to "Insert" and "Shapes" and drawing triangles, arrows and various shapes to be animated in the presentation.  The animation is set to dissolve in.  There is audio on every slide.  When I sync the animations, they look fine on the screen as I am syncing them.  When I preview the slide show in Powerpoint, they look fine.  When I preview in Articulate or Publisher, some of them work fine.  Others are on the screen at the beginning of the slide...the animations appear to be ignored?  What would cause that?  I changed the animations to "Appear" as I know that works...same issue.  So, I saved the images as png images, and rebuilt the slides and reanimated them.  That worked fine except since the shapes are now saved as images, on the colored background, you can make out the subtle rectangle shape of the imported images that, for instance, surrounds the drawn triangle that was converted to a png.  Any suggestions?