When I use SWFObject the flash file is not perfectly inserted into the div, there are some pixels on the left and right side of the swf. This area is filled with the color of background color property.
I try the value "transparent" but then green shows up...
it might just be the way your swf was created, but if you want you can set the background of the Flash Player to be transparent by using:
so.addParam("wmode", "transparent");
but it's usually better to simply match the bg color of the page with that of your flash movie, as using the wmode parameter can decrease performance by quite a bit sometimes.
I always have a large blank square while my Flash movie is loading. Can the transparency values be used to have a .jpg image show from underneath the Flash while it's loading?
I've been trying to get it to work by placing the Flash in a table with an image set as the table background, but it doesn't seem to be doing the transparency correctly. Any way to do this?
sure you can do that if you want... if you are having loading problems, you should consider using a preloader on your swf though, instead of doing strange html hacks like this.
As Geoff suggested - you should use a preloader. Also, Flash loads frame by frame - so if your first frame only has a 10kb image on it, it will show up after the 10k is downloaded.